18916538 has 8 divisors (see below), whose sum is σ = 28483488. Its totient is φ = 9422044.

The previous prime is 18916519. The next prime is 18916553. The reversal of 18916538 is 83561981.

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

It is a junction number, because it is equal to n+sod(n) for n = 18916495 and 18916504.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17456 + ... + 18507.

It is an arithmetic number, because the mean of its divisors is an integer number (3560436).

Almost surely, 2^18916538 is an apocalyptic number.

18916538 is a deficient number, since it is larger than the sum of its proper divisors (9566950).

18916538 is a wasteful number, since it uses less digits than its factorization.

18916538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36228.

The product of its digits is 51840, while the sum is 41.

The square root of 18916538 is about 4349.3146586560. The cubic root of 18916538 is about 266.4488718215.

The spelling of 18916538 in words is "eighteen million, nine hundred sixteen thousand, five hundred thirty-eight".