2156766778479 has 8 divisors (see below), whose sum is σ = 2875696037632. Its totient is φ = 1437841019160.

The previous prime is 2156766778477. The next prime is 2156766778483. The reversal of 2156766778479 is 9748776676512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2156766778479 - 2¹ = 2156766778477 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2156766778479.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2156766778471) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1431624 + ... + 2522514.

It is an arithmetic number, because the mean of its divisors is an integer number (359462004704).

Almost surely, 2^{2156766778479} is an apocalyptic number.

2156766778479 is a deficient number, since it is larger than the sum of its proper divisors (718929259153).

2156766778479 is a wasteful number, since it uses less digits than its factorization.

2156766778479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1749917.

The product of its digits is 1493614080, while the sum is 75.

The spelling of 2156766778479 in words is "two trillion, one hundred fifty-six billion, seven hundred sixty-six million, seven hundred seventy-eight thousand, four hundred seventy-nine".