1276155664 has 40 divisors (see below), whose sum is σ = 2846137280. Its totient is φ = 542982528.

The previous prime is 1276155659. The next prime is 1276155721. The reversal of 1276155664 is 4665516721.

It is a self number, because there is not a number n which added to its sum of digits gives 1276155664.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25419 + ... + 56554.

It is an arithmetic number, because the mean of its divisors is an integer number (71153432).

Almost surely, 2^1276155664 is an apocalyptic number.

1276155664 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

1276155664 is an abundant number, since it is smaller than the sum of its proper divisors (1569981616).

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

1276155664 is a wasteful number, since it uses less digits than its factorization.

1276155664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82127 (or 82121 counting only the distinct ones).

The product of its digits is 302400, while the sum is 43.

The square root of 1276155664 is about 35723.3210102308. The cubic root of 1276155664 is about 1084.6789635395.

The spelling of 1276155664 in words is "one billion, two hundred seventy-six million, one hundred fifty-five thousand, six hundred sixty-four".