1264721720 has 16 divisors (see below), whose sum is σ = 2845623960. Its totient is φ = 505888672.

The previous prime is 1264721683. The next prime is 1264721741. The reversal of 1264721720 is 271274621.

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, 15808982 + ... + 15809061.

Almost surely, 2^1264721720 is an apocalyptic number.

1264721720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1264721720 is an abundant number, since it is smaller than the sum of its proper divisors (1580902240).

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

1264721720 is a wasteful number, since it uses less digits than its factorization.

1264721720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31618054 (or 31618050 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 32.

The square root of 1264721720 is about 35562.9262013125. The cubic root of 1264721720 is about 1081.4297821273.

The spelling of 1264721720 in words is "one billion, two hundred sixty-four million, seven hundred twenty-one thousand, seven hundred twenty".