261392000 has 192 divisors, whose sum is σ = 711027720. Its totient is φ = 95232000.

The previous prime is 261391997. The next prime is 261392009. The reversal of 261392000 is 293162.

It can be written as a sum of positive squares in 4 ways, for example, as 113720896 + 147671104 = 10664^2 + 12152^2 .

It is not an unprimeable number, because it can be changed into a prime (261392009) 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 23 ways as a sum of consecutive naturals, for example, 8431985 + ... + 8432015.

Almost surely, 2^261392000 is an apocalyptic number.

261392000 is a gapful number since it is divisible by the number (20) 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 261392000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (355513860).

261392000 is an abundant number, since it is smaller than the sum of its proper divisors (449635720).

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

261392000 is an equidigital number, since it uses as much as digits as its factorization.

261392000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108 (or 55 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 261392000 is about 16167.6219649026. The cubic root of 261392000 is about 639.3874347138.

The spelling of 261392000 in words is "two hundred sixty-one million, three hundred ninety-two thousand".