261572872 has 16 divisors (see below), whose sum is σ = 535035600. Its totient is φ = 118896720.

The previous prime is 261572851. The next prime is 261572887. The reversal of 261572872 is 278275162.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1486122 + ... + 1486297.

It is an arithmetic number, because the mean of its divisors is an integer number (33439725).

Almost surely, 2^261572872 is an apocalyptic number.

261572872 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

261572872 is an abundant number, since it is smaller than the sum of its proper divisors (273462728).

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

261572872 is a wasteful number, since it uses less digits than its factorization.

261572872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2972436 (or 2972432 counting only the distinct ones).

The product of its digits is 94080, while the sum is 40.

The square root of 261572872 is about 16173.2146464455. The cubic root of 261572872 is about 639.5348768952.

The spelling of 261572872 in words is "two hundred sixty-one million, five hundred seventy-two thousand, eight hundred seventy-two".