21279996 has 36 divisors (see below), whose sum is σ = 55785912. Its totient is φ = 7093008.

The previous prime is 21279959. The next prime is 21280001. The reversal of 21279996 is 69997212.

21279996 is nontrivially palindromic in base 7.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is an unprimeable number.

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, 9975 + ... + 11918.

Almost surely, 2^21279996 is an apocalyptic number.

It is an amenable number.

21279996 is an abundant number, since it is smaller than the sum of its proper divisors (34505916).

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

21279996 is a wasteful number, since it uses less digits than its factorization.

21279996 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21912 (or 21898 counting only the distinct ones).

The product of its digits is 122472, while the sum is 45.

The square root of 21279996 is about 4613.0246043133. The cubic root of 21279996 is about 277.1131790842.

It can be divided in two parts, 212 and 79996, that added together give a palindrome (80208).

The spelling of 21279996 in words is "twenty-one million, two hundred seventy-nine thousand, nine hundred ninety-six".