261161263256 has 16 divisors (see below), whose sum is σ = 490095556440. Its totient is φ = 130469114880.

The previous prime is 261161263219. The next prime is 261161263291. The reversal of 261161263256 is 652362161162.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13929641 + ... + 13948376.

Almost surely, 2^261161263256 is an apocalyptic number.

It is an amenable number.

261161263256 is a deficient number, since it is larger than the sum of its proper divisors (228934293184).

261161263256 is a wasteful number, since it uses less digits than its factorization.

261161263256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27879194 (or 27879190 counting only the distinct ones).

The product of its digits is 155520, while the sum is 41.

The spelling of 261161263256 in words is "two hundred sixty-one billion, one hundred sixty-one million, two hundred sixty-three thousand, two hundred fifty-six".