21335679 has 6 divisors (see below), whose sum is σ = 30818216. Its totient is φ = 14223780.

The previous prime is 21335647. The next prime is 21335683. The reversal of 21335679 is 97653312.

It is not a de Polignac number, because 21335679 - 2⁵ = 21335647 is a prime.

It is a super-2 number, since 2×21335679² = 910422396782082, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21335179) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1185307 + ... + 1185324.

Almost surely, 2^21335679 is an apocalyptic number.

21335679 is a deficient number, since it is larger than the sum of its proper divisors (9482537).

21335679 is a wasteful number, since it uses less digits than its factorization.

21335679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2370637 (or 2370634 counting only the distinct ones).

The product of its digits is 34020, while the sum is 36.

The square root of 21335679 is about 4619.0560724027. The cubic root of 21335679 is about 277.3546743329.

The spelling of 21335679 in words is "twenty-one million, three hundred thirty-five thousand, six hundred seventy-nine".