1557242790 has 32 divisors (see below), whose sum is σ = 3779382240. Its totient is φ = 410598144.

The previous prime is 1557242777. The next prime is 1557242803. The reversal of 1557242790 is 972427551.

It is an interprime number because it is at equal distance from previous prime (1557242777) and next prime (1557242803).

It is a Curzon number.

It is a congruent number.

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, 288949 + ... + 294288.

It is an arithmetic number, because the mean of its divisors is an integer number (118105695).

Almost surely, 2^1557242790 is an apocalyptic number.

1557242790 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1557242790 is an abundant number, since it is smaller than the sum of its proper divisors (2222139450).

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

1557242790 is a wasteful number, since it uses less digits than its factorization.

1557242790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 583336.

The product of its (nonzero) digits is 176400, while the sum is 42.

The square root of 1557242790 is about 39461.9156909545. The cubic root of 1557242790 is about 1159.0943163466.

The spelling of 1557242790 in words is "one billion, five hundred fifty-seven million, two hundred forty-two thousand, seven hundred ninety".