15857287157 has 4 divisors (see below), whose sum is σ = 15896831916. Its totient is φ = 15817742400.

The previous prime is 15857287123. The next prime is 15857287169. The reversal of 15857287157 is 75178275851.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10446066436 + 5411220721 = 102206^2 + 73561^2 .

It is a cyclic number.

It is not a de Polignac number, because 15857287157 - 2⁶ = 15857287093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15857287657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19771778 + ... + 19772579.

It is an arithmetic number, because the mean of its divisors is an integer number (3974207979).

Almost surely, 2^15857287157 is an apocalyptic number.

It is an amenable number.

15857287157 is a deficient number, since it is larger than the sum of its proper divisors (39544759).

15857287157 is an equidigital number, since it uses as much as digits as its factorization.

15857287157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39544758.

The product of its digits is 5488000, while the sum is 56.

The spelling of 15857287157 in words is "fifteen billion, eight hundred fifty-seven million, two hundred eighty-seven thousand, one hundred fifty-seven".