261657071157025 has 24 divisors (see below), whose sum is σ = 324675639277344. Its totient is φ = 209183166172800.

The previous prime is 261657071157019. The next prime is 261657071157043. The reversal of 261657071157025 is 520751170756162.

It is not a de Polignac number, because 261657071157025 - 2⁵ = 261657071156993 is a prime.

It is a hoax number, since the sum of its digits (55) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3095721765 + ... + 3095806285.

It is an arithmetic number, because the mean of its divisors is an integer number (13528151636556).

Almost surely, 2^{261657071157025} is an apocalyptic number.

261657071157025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

261657071157025 is a deficient number, since it is larger than the sum of its proper divisors (63018568120319).

261657071157025 is a wasteful number, since it uses less digits than its factorization.

261657071157025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167361 (or 167356 counting only the distinct ones).

The product of its (nonzero) digits is 6174000, while the sum is 55.

The spelling of 261657071157025 in words is "two hundred sixty-one trillion, six hundred fifty-seven billion, seventy-one million, one hundred fifty-seven thousand, twenty-five".