157685609 has 2 divisors, whose sum is σ = 157685610. Its totient is φ = 157685608.

The previous prime is 157685599. The next prime is 157685651. The reversal of 157685609 is 906586751.

157685609 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 153685609 + 4000000 = 12397^2 + 2000^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-157685609 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (157685699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78842804 + 78842805.

It is an arithmetic number, because the mean of its divisors is an integer number (78842805).

Almost surely, 2^157685609 is an apocalyptic number.

It is an amenable number.

157685609 is a deficient number, since it is larger than the sum of its proper divisors (1).

157685609 is an equidigital number, since it uses as much as digits as its factorization.

157685609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 453600, while the sum is 47.

The square root of 157685609 is about 12557.2930602101. The cubic root of 157685609 is about 540.2532065841.

The spelling of 157685609 in words is "one hundred fifty-seven million, six hundred eighty-five thousand, six hundred nine".