1557138753 has 6 divisors (see below), whose sum is σ = 2249200434. Its totient is φ = 1038092496.

The previous prime is 1557138733. The next prime is 1557138761. The reversal of 1557138753 is 3578317551.

1557138753 is a `hidden beast` number, since 1 + 5 + 571 + 3 + 8 + 75 + 3 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1109689344 + 447449409 = 33312^2 + 21153^2 .

It is not a de Polignac number, because 1557138753 - 2⁶ = 1557138689 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1557138699 and 1557138708.

It is not an unprimeable number, because it can be changed into a prime (1557138703) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 86507700 + ... + 86507717.

It is an arithmetic number, because the mean of its divisors is an integer number (374866739).

Almost surely, 2^1557138753 is an apocalyptic number.

It is an amenable number.

1557138753 is a deficient number, since it is larger than the sum of its proper divisors (692061681).

1557138753 is a wasteful number, since it uses less digits than its factorization.

1557138753 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173015423 (or 173015420 counting only the distinct ones).

The product of its digits is 441000, while the sum is 45.

The square root of 1557138753 is about 39460.5974739359. The cubic root of 1557138753 is about 1159.0685033345.

The spelling of 1557138753 in words is "one billion, five hundred fifty-seven million, one hundred thirty-eight thousand, seven hundred fifty-three".