21653934 has 32 divisors (see below), whose sum is σ = 45674496. Its totient is φ = 6833760.

The previous prime is 21653927. The next prime is 21653941. The reversal of 21653934 is 43935612.

It is an interprime number because it is at equal distance from previous prime (21653927) and next prime (21653941).

It is a junction number, because it is equal to n+sod(n) for n = 21653895 and 21653904.

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 15 ways as a sum of consecutive naturals, for example, 7504 + ... + 9980.

It is an arithmetic number, because the mean of its divisors is an integer number (1427328).

Almost surely, 2^21653934 is an apocalyptic number.

21653934 is an abundant number, since it is smaller than the sum of its proper divisors (24020562).

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

21653934 is a wasteful number, since it uses less digits than its factorization.

21653934 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2560.

The product of its digits is 19440, while the sum is 33.

The square root of 21653934 is about 4653.3787724620. The cubic root of 21653934 is about 278.7269331459.

The spelling of 21653934 in words is "twenty-one million, six hundred fifty-three thousand, nine hundred thirty-four".