21934931 has 4 divisors (see below), whose sum is σ = 21951672. Its totient is φ = 21918192.

The previous prime is 21934907. The next prime is 21934937. The reversal of 21934931 is 13943912.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21934931 - 2¹⁰ = 21933907 is a prime.

It is a super-2 number, since 2×21934931² = 962282395949522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21934937) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6221 + ... + 9086.

It is an arithmetic number, because the mean of its divisors is an integer number (5487918).

Almost surely, 2^21934931 is an apocalyptic number.

21934931 is a deficient number, since it is larger than the sum of its proper divisors (16741).

21934931 is a wasteful number, since it uses less digits than its factorization.

21934931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16740.

The product of its digits is 5832, while the sum is 32.

The square root of 21934931 is about 4683.4742446180. The cubic root of 21934931 is about 279.9274089032.

The spelling of 21934931 in words is "twenty-one million, nine hundred thirty-four thousand, nine hundred thirty-one".