21917093 has 12 divisors (see below), whose sum is σ = 24872064. Its totient is φ = 19278600.

The previous prime is 21917023. The next prime is 21917113. The reversal of 21917093 is 39071912.

It is a happy number.

It is not a de Polignac number, because 21917093 - 2²⁴ = 5139877 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21917003) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 830 + ... + 6672.

It is an arithmetic number, because the mean of its divisors is an integer number (2072672).

Almost surely, 2^21917093 is an apocalyptic number.

It is an amenable number.

21917093 is a deficient number, since it is larger than the sum of its proper divisors (2954971).

21917093 is a wasteful number, since it uses less digits than its factorization.

21917093 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5896 (or 5885 counting only the distinct ones).

The product of its (nonzero) digits is 3402, while the sum is 32.

The square root of 21917093 is about 4681.5695017804. The cubic root of 21917093 is about 279.8515071478.

The spelling of 21917093 in words is "twenty-one million, nine hundred seventeen thousand, ninety-three".