18772157 has 2 divisors, whose sum is σ = 18772158. Its totient is φ = 18772156.

The previous prime is 18772141. The next prime is 18772177. The reversal of 18772157 is 75127781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17799961 + 972196 = 4219^2 + 986^2 .

It is a cyclic number.

It is not a de Polignac number, because 18772157 - 2⁴ = 18772141 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18772157.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18772177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9386078 + 9386079.

It is an arithmetic number, because the mean of its divisors is an integer number (9386079).

Almost surely, 2^18772157 is an apocalyptic number.

It is an amenable number.

18772157 is a deficient number, since it is larger than the sum of its proper divisors (1).

18772157 is an equidigital number, since it uses as much as digits as its factorization.

18772157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27440, while the sum is 38.

The square root of 18772157 is about 4332.6847335111. The cubic root of 18772157 is about 265.7692469954.

The spelling of 18772157 in words is "eighteen million, seven hundred seventy-two thousand, one hundred fifty-seven".