21612634 has 8 divisors (see below), whose sum is σ = 32524128. Its totient is φ = 10771260.

The previous prime is 21612623. The next prime is 21612637. The reversal of 21612634 is 43621612.

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 = 21612599 and 21612608.

It is not an unprimeable number, because it can be changed into a prime (21612637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16752 + ... + 17995.

It is an arithmetic number, because the mean of its divisors is an integer number (4065516).

Almost surely, 2^21612634 is an apocalyptic number.

21612634 is a deficient number, since it is larger than the sum of its proper divisors (10911494).

21612634 is a wasteful number, since it uses less digits than its factorization.

21612634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35060.

The product of its digits is 1728, while the sum is 25.

The square root of 21612634 is about 4648.9390187440. The cubic root of 21612634 is about 278.5496174276.

The spelling of 21612634 in words is "twenty-one million, six hundred twelve thousand, six hundred thirty-four".