21421626 has 16 divisors (see below), whose sum is σ = 45098400. Its totient is φ = 6764688.

The previous prime is 21421619. The next prime is 21421627. The reversal of 21421626 is 62612412.

It is a junction number, because it is equal to n+sod(n) for n = 21421596 and 21421605.

It is not an unprimeable number, because it can be changed into a prime (21421627) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 93841 + ... + 94068.

It is an arithmetic number, because the mean of its divisors is an integer number (2818650).

Almost surely, 2^21421626 is an apocalyptic number.

21421626 is an abundant number, since it is smaller than the sum of its proper divisors (23676774).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21421626 is a wasteful number, since it uses less digits than its factorization.

21421626 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187933.

The product of its digits is 1152, while the sum is 24.

The square root of 21421626 is about 4628.3502460380. The cubic root of 21421626 is about 277.7266000768.

The spelling of 21421626 in words is "twenty-one million, four hundred twenty-one thousand, six hundred twenty-six".