1257321864 has 64 divisors (see below), whose sum is σ = 3368672640. Its totient is φ = 390044160.

The previous prime is 1257321829. The next prime is 1257321881. The reversal of 1257321864 is 4681237521.

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10357 + ... + 51204.

It is an arithmetic number, because the mean of its divisors is an integer number (52635510).

Almost surely, 2^1257321864 is an apocalyptic number.

It is an amenable number.

1257321864 is an abundant number, since it is smaller than the sum of its proper divisors (2111350776).

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

1257321864 is a wasteful number, since it uses less digits than its factorization.

1257321864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61630 (or 61626 counting only the distinct ones).

The product of its digits is 80640, while the sum is 39.

The square root of 1257321864 is about 35458.7346643955. The cubic root of 1257321864 is about 1079.3165154177.

The spelling of 1257321864 in words is "one billion, two hundred fifty-seven million, three hundred twenty-one thousand, eight hundred sixty-four".