18216957 has 8 divisors (see below), whose sum is σ = 26497440. Its totient is φ = 11040560.

The previous prime is 18216941. The next prime is 18216971. The reversal of 18216957 is 75961281.

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

It is a cyclic number.

It is not a de Polignac number, because 18216957 - 2⁴ = 18216941 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18216917) 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, 275982 + ... + 276047.

It is an arithmetic number, because the mean of its divisors is an integer number (3312180).

Almost surely, 2^18216957 is an apocalyptic number.

It is an amenable number.

18216957 is a deficient number, since it is larger than the sum of its proper divisors (8280483).

18216957 is a wasteful number, since it uses less digits than its factorization.

18216957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 552043.

The product of its digits is 30240, while the sum is 39.

The square root of 18216957 is about 4268.1327298949. The cubic root of 18216957 is about 263.1228781920.

It can be divided in two parts, 1821 and 6957, that added together give a palindrome (8778).

The spelling of 18216957 in words is "eighteen million, two hundred sixteen thousand, nine hundred fifty-seven".