1557065638 has 16 divisors (see below), whose sum is σ = 2448711936. Its totient is φ = 741149640.

The previous prime is 1557065617. The next prime is 1557065639. The reversal of 1557065638 is 8365607551.

It is a Harshad number since it is a multiple of its sum of digits (46).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1557065639) 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, 70506 + ... + 89917.

It is an arithmetic number, because the mean of its divisors is an integer number (153044496).

Almost surely, 2^1557065638 is an apocalyptic number.

1557065638 is a deficient number, since it is larger than the sum of its proper divisors (891646298).

1557065638 is a wasteful number, since it uses less digits than its factorization.

1557065638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160659.

The product of its (nonzero) digits is 756000, while the sum is 46.

The square root of 1557065638 is about 39459.6710325872. The cubic root of 1557065638 is about 1159.0503618084.

The spelling of 1557065638 in words is "one billion, five hundred fifty-seven million, sixty-five thousand, six hundred thirty-eight".