21320926 has 24 divisors (see below), whose sum is σ = 37011240. Its totient is φ = 9179280.

The previous prime is 21320921. The next prime is 21320947. The reversal of 21320926 is 62902312.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21320926.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21320921) 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 11 ways as a sum of consecutive naturals, for example, 2280 + ... + 6916.

It is an arithmetic number, because the mean of its divisors is an integer number (1542135).

Almost surely, 2^21320926 is an apocalyptic number.

21320926 is a deficient number, since it is larger than the sum of its proper divisors (15690314).

21320926 is a wasteful number, since it uses less digits than its factorization.

21320926 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4680 (or 4669 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 21320926 is about 4617.4588249382. The cubic root of 21320926 is about 277.2907320355.

The spelling of 21320926 in words is "twenty-one million, three hundred twenty thousand, nine hundred twenty-six".