1264881620 has 12 divisors (see below), whose sum is σ = 2656251444. Its totient is φ = 505952640.

The previous prime is 1264881613. The next prime is 1264881637. The reversal of 1264881620 is 261884621.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 582836164 + 682045456 = 24142^2 + 26116^2 .

It is a super-2 number, since 2×1264881620² = 3199851025227648800, which contains 22 as substring.

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, 31622021 + ... + 31622060.

It is an arithmetic number, because the mean of its divisors is an integer number (221354287).

Almost surely, 2^1264881620 is an apocalyptic number.

1264881620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1264881620 is an abundant number, since it is smaller than the sum of its proper divisors (1391369824).

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

1264881620 is a wasteful number, since it uses less digits than its factorization.

1264881620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63244090 (or 63244088 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 38.

The square root of 1264881620 is about 35565.1742579732. The cubic root of 1264881620 is about 1081.4753556139.

The spelling of 1264881620 in words is "one billion, two hundred sixty-four million, eight hundred eighty-one thousand, six hundred twenty".