261382464 has 252 divisors, whose sum is σ = 906438624. Its totient is φ = 74680704.

The previous prime is 261382439. The next prime is 261382469. The reversal of 261382464 is 464283162.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It is a tau number, because it is divible by the number of its divisors (252).

It is a super-2 number, since 2×261382464² = 136641584973422592, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

Its product of digits (55296) is a multiple of the sum of its prime divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261382469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 37340349 + ... + 37340355.

Almost surely, 2^261382464 is an apocalyptic number.

261382464 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261382464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (453219312).

261382464 is an abundant number, since it is smaller than the sum of its proper divisors (645056160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261382464 is an frugal number, since it uses more digits than its factorization.

261382464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62 (or 12 counting only the distinct ones).

The product of its digits is 55296, while the sum is 36.

The square root of 261382464 is about 16167.3270518042. The cubic root of 261382464 is about 639.3796593257.

The spelling of 261382464 in words is "two hundred sixty-one million, three hundred eighty-two thousand, four hundred sixty-four".