157642813 has 4 divisors (see below), whose sum is σ = 159542208. Its totient is φ = 155743420.

The previous prime is 157642801. The next prime is 157642817. The reversal of 157642813 is 318246751.

157642813 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 318246751 = 19 ⋅16749829.

It is a cyclic number.

It is not a de Polignac number, because 157642813 - 2⁹ = 157642301 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 (157642817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 949573 + ... + 949738.

It is an arithmetic number, because the mean of its divisors is an integer number (39885552).

Almost surely, 2^157642813 is an apocalyptic number.

It is an amenable number.

157642813 is a deficient number, since it is larger than the sum of its proper divisors (1899395).

157642813 is an equidigital number, since it uses as much as digits as its factorization.

157642813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1899394.

The product of its digits is 40320, while the sum is 37.

The square root of 157642813 is about 12555.5889149016. The cubic root of 157642813 is about 540.2043271115.

The spelling of 157642813 in words is "one hundred fifty-seven million, six hundred forty-two thousand, eight hundred thirteen".