2561764975856 has 20 divisors (see below), whose sum is σ = 5007343711872. Its totient is φ = 1269547243776.

The previous prime is 2561764975807. The next prime is 2561764975867. The reversal of 2561764975856 is 6585794671652.

It is a self number, because there is not a number n which added to its sum of digits gives 2561764975856.

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, 708450896 + ... + 708454511.

Almost surely, 2^{2561764975856} is an apocalyptic number.

It is an amenable number.

2561764975856 is a deficient number, since it is larger than the sum of its proper divisors (2445578736016).

2561764975856 is a wasteful number, since it uses less digits than its factorization.

2561764975856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1416905528 (or 1416905522 counting only the distinct ones).

The product of its digits is 762048000, while the sum is 71.

The spelling of 2561764975856 in words is "two trillion, five hundred sixty-one billion, seven hundred sixty-four million, nine hundred seventy-five thousand, eight hundred fifty-six".