261357422520 has 64 divisors (see below), whose sum is σ = 785364203520. Its totient is φ = 69580473984.

The previous prime is 261357422471. The next prime is 261357422533. The reversal of 261357422520 is 25224753162.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1721212 + ... + 1866891.

It is an arithmetic number, because the mean of its divisors is an integer number (12271315680).

Almost surely, 2^261357422520 is an apocalyptic number.

261357422520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261357422520 is an abundant number, since it is smaller than the sum of its proper divisors (524006781000).

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

261357422520 is a wasteful number, since it uses less digits than its factorization.

261357422520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3588724 (or 3588720 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 39.

The spelling of 261357422520 in words is "two hundred sixty-one billion, three hundred fifty-seven million, four hundred twenty-two thousand, five hundred twenty".