261477216 has 288 divisors, whose sum is σ = 999468288. Its totient is φ = 62622720.

The previous prime is 261477211. The next prime is 261477247. The reversal of 261477216 is 612774162.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×261477216² = 136740668974221312, 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.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261477211) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 287835 + ... + 288741.

It is an arithmetic number, because the mean of its divisors is an integer number (3470376).

Almost surely, 2^261477216 is an apocalyptic number.

261477216 is a gapful number since it is divisible by the number (26) 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 261477216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (499734144).

261477216 is an abundant number, since it is smaller than the sum of its proper divisors (737991072).

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

261477216 is a wasteful number, since it uses less digits than its factorization.

261477216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 954 (or 943 counting only the distinct ones).

The product of its digits is 28224, while the sum is 36.

The square root of 261477216 is about 16170.2571408126. The cubic root of 261477216 is about 639.4569090661.

The spelling of 261477216 in words is "two hundred sixty-one million, four hundred seventy-seven thousand, two hundred sixteen".