157209187 has 4 divisors (see below), whose sum is σ = 157895920. Its totient is φ = 156522456.

The previous prime is 157209167. The next prime is 157209191. The reversal of 157209187 is 781902751.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-157209187 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (157209127) 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, 343023 + ... + 343480.

It is an arithmetic number, because the mean of its divisors is an integer number (39473980).

Almost surely, 2^157209187 is an apocalyptic number.

157209187 is a deficient number, since it is larger than the sum of its proper divisors (686733).

157209187 is an equidigital number, since it uses as much as digits as its factorization.

157209187 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 686732.

The product of its (nonzero) digits is 35280, while the sum is 40.

The square root of 157209187 is about 12538.3087775027. The cubic root of 157209187 is about 539.7085613027.

The spelling of 157209187 in words is "one hundred fifty-seven million, two hundred nine thousand, one hundred eighty-seven".