1257742920 has 64 divisors (see below), whose sum is σ = 4312264320. Its totient is φ = 287483904.

The previous prime is 1257742903. The next prime is 1257742931. The reversal of 1257742920 is 292477521.

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, 747817 + ... + 749496.

It is an arithmetic number, because the mean of its divisors is an integer number (67379130).

Almost surely, 2^1257742920 is an apocalyptic number.

1257742920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1257742920 is an abundant number, since it is smaller than the sum of its proper divisors (3054521400).

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

1257742920 is a wasteful number, since it uses less digits than its factorization.

1257742920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1497334 (or 1497330 counting only the distinct ones).

The product of its (nonzero) digits is 70560, while the sum is 39.

The square root of 1257742920 is about 35464.6714351057. The cubic root of 1257742920 is about 1079.4369836360.

The spelling of 1257742920 in words is "one billion, two hundred fifty-seven million, seven hundred forty-two thousand, nine hundred twenty".