157396681 has 4 divisors (see below), whose sum is σ = 169504132. Its totient is φ = 145289232.

The previous prime is 157396661. The next prime is 157396691. The reversal of 157396681 is 186693751.

It is a happy number.

157396681 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 an emirpimes, since its reverse is a distinct semiprime: 186693751 = 449 ⋅415799.

It can be written as a sum of positive squares in 2 ways, for example, as 15405625 + 141991056 = 3925^2 + 11916^2 .

It is a cyclic number.

It is not a de Polignac number, because 157396681 - 2⁵ = 157396649 is a prime.

It is a super-2 number, since 2×157396681² = 49547430379631522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (157396651) 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, 6053706 + ... + 6053731.

It is an arithmetic number, because the mean of its divisors is an integer number (42376033).

Almost surely, 2^157396681 is an apocalyptic number.

It is an amenable number.

157396681 is a deficient number, since it is larger than the sum of its proper divisors (12107451).

157396681 is a wasteful number, since it uses less digits than its factorization.

157396681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12107450.

The product of its digits is 272160, while the sum is 46.

The square root of 157396681 is about 12545.7833952289. The cubic root of 157396681 is about 539.9230354416.

The spelling of 157396681 in words is "one hundred fifty-seven million, three hundred ninety-six thousand, six hundred eighty-one".