157709999 has 4 divisors (see below), whose sum is σ = 157812720. Its totient is φ = 157607280.

The previous prime is 157709971. The next prime is 157710001. The reversal of 157709999 is 999907751.

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

It is a cyclic number.

It is not a de Polignac number, because 157709999 - 2²⁰ = 156661423 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 (157706999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49022 + ... + 52139.

It is an arithmetic number, because the mean of its divisors is an integer number (39453180).

Almost surely, 2^157709999 is an apocalyptic number.

157709999 is a deficient number, since it is larger than the sum of its proper divisors (102721).

157709999 is a wasteful number, since it uses less digits than its factorization.

157709999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102720.

The product of its (nonzero) digits is 1607445, while the sum is 56.

The square root of 157709999 is about 12558.2641714530. The cubic root of 157709999 is about 540.2810596784.

The spelling of 157709999 in words is "one hundred fifty-seven million, seven hundred nine thousand, nine hundred ninety-nine".