21411968 has 24 divisors (see below), whose sum is σ = 42761205. Its totient is φ = 10679808.

The previous prime is 21411953. The next prime is 21411983. The reversal of 21411968 is 86911412.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It is an interprime number because it is at equal distance from previous prime (21411953) and next prime (21411983).

It can be written as a sum of positive squares in 2 ways, for example, as 16711744 + 4700224 = 4088^2 + 2168^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=3272.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 52148 + ... + 52556.

Almost surely, 2^21411968 is an apocalyptic number.

It is an amenable number.

21411968 is a deficient number, since it is larger than the sum of its proper divisors (21349237).

21411968 is an frugal number, since it uses more digits than its factorization.

21411968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 832 (or 411 counting only the distinct ones).

The product of its digits is 3456, while the sum is 32.

The square root of 21411968 is about 4627.3067760848. The cubic root of 21411968 is about 277.6848558645.

Multiplying 21411968 by its sum of digits (32), we get a square (685182976 = 26176²).

21411968 divided by its sum of digits (32) gives a square (669124 = 818²).

The spelling of 21411968 in words is "twenty-one million, four hundred eleven thousand, nine hundred sixty-eight".