2661256516164 has 48 divisors (see below), whose sum is σ = 6296267355840. Its totient is φ = 874781389440.

The previous prime is 2661256516129. The next prime is 2661256516169. The reversal of 2661256516164 is 4616156521662.

It is not an unprimeable number, because it can be changed into a prime (2661256516169) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4545339 + ... + 5097314.

It is an arithmetic number, because the mean of its divisors is an integer number (131172236580).

Almost surely, 2^{2661256516164} is an apocalyptic number.

It is an amenable number.

2661256516164 is an abundant number, since it is smaller than the sum of its proper divisors (3635010839676).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2661256516164 is a wasteful number, since it uses less digits than its factorization.

2661256516164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9642980 (or 9642978 counting only the distinct ones).

The product of its digits is 3110400, while the sum is 51.

The spelling of 2661256516164 in words is "two trillion, six hundred sixty-one billion, two hundred fifty-six million, five hundred sixteen thousand, one hundred sixty-four".