21906934 has 8 divisors (see below), whose sum is σ = 37554768. Its totient is φ = 9388680.

The previous prime is 21906917. The next prime is 21906949. The reversal of 21906934 is 43960912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21906934.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 782377 + ... + 782404.

It is an arithmetic number, because the mean of its divisors is an integer number (4694346).

Almost surely, 2^21906934 is an apocalyptic number.

21906934 is a deficient number, since it is larger than the sum of its proper divisors (15647834).

21906934 is a wasteful number, since it uses less digits than its factorization.

21906934 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1564790.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 21906934 is about 4680.4843766431. The cubic root of 21906934 is about 279.8082615885.

The spelling of 21906934 in words is "twenty-one million, nine hundred six thousand, nine hundred thirty-four".