18722157 has 8 divisors (see below), whose sum is σ = 25543584. Its totient is φ = 12191088.

The previous prime is 18722149. The next prime is 18722159. The reversal of 18722157 is 75122781.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18722157 - 2³ = 18722149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18722159) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72438 + ... + 72695.

It is an arithmetic number, because the mean of its divisors is an integer number (3192948).

Almost surely, 2^18722157 is an apocalyptic number.

It is an amenable number.

18722157 is a deficient number, since it is larger than the sum of its proper divisors (6821427).

18722157 is a wasteful number, since it uses less digits than its factorization.

18722157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145179.

The product of its digits is 7840, while the sum is 33.

The square root of 18722157 is about 4326.9107917774. The cubic root of 18722157 is about 265.5330766952.

The spelling of 18722157 in words is "eighteen million, seven hundred twenty-two thousand, one hundred fifty-seven".