21983679 has 6 divisors (see below), whose sum is σ = 31754216. Its totient is φ = 14655780.

The previous prime is 21983671. The next prime is 21983683. The reversal of 21983679 is 97638912.

It is not a de Polignac number, because 21983679 - 2³ = 21983671 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21983671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1221307 + ... + 1221324.

Almost surely, 2^21983679 is an apocalyptic number.

21983679 is a deficient number, since it is larger than the sum of its proper divisors (9770537).

21983679 is a wasteful number, since it uses less digits than its factorization.

21983679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2442637 (or 2442634 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The square root of 21983679 is about 4688.6756125797. The cubic root of 21983679 is about 280.1346248874.

The spelling of 21983679 in words is "twenty-one million, nine hundred eighty-three thousand, six hundred seventy-nine".