2156694884565 has 16 divisors (see below), whose sum is σ = 3716151186048. Its totient is φ = 1061757481536.

The previous prime is 2156694884557. The next prime is 2156694884579. The reversal of 2156694884565 is 5654884966512.

It is not a de Polignac number, because 2156694884565 - 2³ = 2156694884557 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2156694884565.

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, 5529986689 + ... + 5529987078.

It is an arithmetic number, because the mean of its divisors is an integer number (232259449128).

Almost surely, 2^{2156694884565} is an apocalyptic number.

It is an amenable number.

2156694884565 is a deficient number, since it is larger than the sum of its proper divisors (1559456301483).

2156694884565 is a wasteful number, since it uses less digits than its factorization.

2156694884565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11059973788.

The product of its digits is 497664000, while the sum is 69.

The spelling of 2156694884565 in words is "two trillion, one hundred fifty-six billion, six hundred ninety-four million, eight hundred eighty-four thousand, five hundred sixty-five".