157715905 has 4 divisors (see below), whose sum is σ = 189259092. Its totient is φ = 126172720.

The previous prime is 157715897. The next prime is 157715911. The reversal of 157715905 is 509517751.

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 80838081 + 76877824 = 8991^2 + 8768^2 .

It is not a de Polignac number, because 157715905 - 2³ = 157715897 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15771586 + ... + 15771595.

It is an arithmetic number, because the mean of its divisors is an integer number (47314773).

Almost surely, 2^157715905 is an apocalyptic number.

It is an amenable number.

157715905 is a deficient number, since it is larger than the sum of its proper divisors (31543187).

157715905 is an equidigital number, since it uses as much as digits as its factorization.

157715905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31543186.

The product of its (nonzero) digits is 55125, while the sum is 40.

The square root of 157715905 is about 12558.4993132141. The cubic root of 157715905 is about 540.2878038293.

The spelling of 157715905 in words is "one hundred fifty-seven million, seven hundred fifteen thousand, nine hundred five".