21636084 has 24 divisors (see below), whose sum is σ = 51438240. Its totient is φ = 7075744.

The previous prime is 21636073. The next prime is 21636089. The reversal of 21636084 is 48063612.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21636089) 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, 16374 + ... + 17645.

It is an arithmetic number, because the mean of its divisors is an integer number (2143260).

Almost surely, 2^21636084 is an apocalyptic number.

It is an amenable number.

21636084 is an abundant number, since it is smaller than the sum of its proper divisors (29802156).

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

21636084 is a wasteful number, since it uses less digits than its factorization.

21636084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34079 (or 34077 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 21636084 is about 4651.4604158264. The cubic root of 21636084 is about 278.6503243801.

Adding to 21636084 its reverse (48063612), we get a palindrome (69699696).

It can be divided in two parts, 2163608 and 4, that added together give a palindrome (2163612).

The spelling of 21636084 in words is "twenty-one million, six hundred thirty-six thousand, eighty-four".