261275221005556 has 12 divisors (see below), whose sum is σ = 457812617243968. Its totient is φ = 130471616078712.

The previous prime is 261275221005521. The next prime is 261275221005571. The reversal of 261275221005556 is 655500122572162.

It is a happy number.

261275221005556 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×261275221005556² (a number of 30 digits) contains 22 as substring.

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, 41498602476 + ... + 41498608771.

Almost surely, 2^{261275221005556} is an apocalyptic number.

It is an amenable number.

261275221005556 is a deficient number, since it is larger than the sum of its proper divisors (196537396238412).

261275221005556 is a wasteful number, since it uses less digits than its factorization.

261275221005556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82997212038 (or 82997212036 counting only the distinct ones).

The product of its (nonzero) digits is 2520000, while the sum is 49.

The spelling of 261275221005556 in words is "two hundred sixty-one trillion, two hundred seventy-five billion, two hundred twenty-one million, five thousand, five hundred fifty-six".