21612734 has 24 divisors (see below), whose sum is σ = 38302632. Its totient is φ = 9066720.

The previous prime is 21612707. The next prime is 21612749. The reversal of 21612734 is 43721612.

It is a super-2 number, since 2×21612734² = 934220541909512, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a congruent number.

It is an unprimeable number.

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, 812 + ... + 6624.

It is an arithmetic number, because the mean of its divisors is an integer number (1595943).

Almost surely, 2^21612734 is an apocalyptic number.

21612734 is a deficient number, since it is larger than the sum of its proper divisors (16689898).

21612734 is a wasteful number, since it uses less digits than its factorization.

21612734 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5852 (or 5839 counting only the distinct ones).

The product of its digits is 2016, while the sum is 26.

The square root of 21612734 is about 4648.9497738737. The cubic root of 21612734 is about 278.5500470362.

The spelling of 21612734 in words is "twenty-one million, six hundred twelve thousand, seven hundred thirty-four".