21912093 has 32 divisors (see below), whose sum is σ = 37355520. Its totient is φ = 12435120.

The previous prime is 21912047. The next prime is 21912097. The reversal of 21912093 is 39021912.

It is not a de Polignac number, because 21912093 - 2⁸ = 21911837 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21912097) 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 31 ways as a sum of consecutive naturals, for example, 35796 + ... + 36402.

It is an arithmetic number, because the mean of its divisors is an integer number (1167360).

Almost surely, 2^21912093 is an apocalyptic number.

It is an amenable number.

21912093 is a deficient number, since it is larger than the sum of its proper divisors (15443427).

21912093 is a wasteful number, since it uses less digits than its factorization.

21912093 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 814 (or 808 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 21912093 is about 4681.0354623737. The cubic root of 21912093 is about 279.8302244599.

The spelling of 21912093 in words is "twenty-one million, nine hundred twelve thousand, ninety-three".