1257047680 has 64 divisors (see below), whose sum is σ = 3434446080. Its totient is φ = 430986240.

The previous prime is 1257047653. The next prime is 1257047683. The reversal of 1257047680 is 867407521.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (1257047683) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 135816 + ... + 144775.

It is an arithmetic number, because the mean of its divisors is an integer number (53663220).

Almost surely, 2^1257047680 is an apocalyptic number.

1257047680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1257047680 is an abundant number, since it is smaller than the sum of its proper divisors (2177398400).

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

1257047680 is an equidigital number, since it uses as much as digits as its factorization.

1257047680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280617 (or 280605 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 40.

The square root of 1257047680 is about 35454.8682129831. The cubic root of 1257047680 is about 1079.2380542477.

The spelling of 1257047680 in words is "one billion, two hundred fifty-seven million, forty-seven thousand, six hundred eighty".