21368426 has 24 divisors (see below), whose sum is σ = 35303520. Its totient is φ = 9672696.

The previous prime is 21368401. The next prime is 21368429. The reversal of 21368426 is 62486312.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21368392 and 21368401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21368429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19571 + ... + 20633.

It is an arithmetic number, because the mean of its divisors is an integer number (1470980).

Almost surely, 2^21368426 is an apocalyptic number.

21368426 is a deficient number, since it is larger than the sum of its proper divisors (13935094).

21368426 is a wasteful number, since it uses less digits than its factorization.

21368426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1130 (or 1107 counting only the distinct ones).

The product of its digits is 13824, while the sum is 32.

The square root of 21368426 is about 4622.5994851382. The cubic root of 21368426 is about 277.4965007810.

The spelling of 21368426 in words is "twenty-one million, three hundred sixty-eight thousand, four hundred twenty-six".