21693926 has 4 divisors (see below), whose sum is σ = 32540892. Its totient is φ = 10846962.

The previous prime is 21693911. The next prime is 21693937. The reversal of 21693926 is 62939612.

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

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21693926.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5423480 + ... + 5423483.

It is an arithmetic number, because the mean of its divisors is an integer number (8135223).

Almost surely, 2^21693926 is an apocalyptic number.

21693926 is a deficient number, since it is larger than the sum of its proper divisors (10846966).

21693926 is a wasteful number, since it uses less digits than its factorization.

21693926 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10846965.

The product of its digits is 34992, while the sum is 38.

The square root of 21693926 is about 4657.6738829592. The cubic root of 21693926 is about 278.8984184179.

The spelling of 21693926 in words is "twenty-one million, six hundred ninety-three thousand, nine hundred twenty-six".