18636516 has 36 divisors (see below), whose sum is σ = 47250112. Its totient is φ = 6193584.

The previous prime is 18636481. The next prime is 18636517. The reversal of 18636516 is 61563681.

It is a happy number.

18636516 is a `hidden beast` number, since 1 + 8 + 636 + 5 + 16 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (18636517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17001 + ... + 18063.

Almost surely, 2^18636516 is an apocalyptic number.

It is an amenable number.

18636516 is an abundant number, since it is smaller than the sum of its proper divisors (28613596).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18636516 is a wasteful number, since it uses less digits than its factorization.

18636516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1560 (or 1555 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 18636516 is about 4317.0031271705. The cubic root of 18636516 is about 265.1275806709.

Subtracting from 18636516 its product of digits (25920), we obtain a square (18610596 = 4314²).

It can be divided in two parts, 186 and 36516, that multiplied together give a palindrome (6791976).

The spelling of 18636516 in words is "eighteen million, six hundred thirty-six thousand, five hundred sixteen".