21964931 has 8 divisors (see below), whose sum is σ = 24126720. Its totient is φ = 19903752.

The previous prime is 21964903. The next prime is 21964937. The reversal of 21964931 is 13946912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21964931 is a prime.

It is a super-2 number, since 2×21964931² = 964916387669522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21964891 and 21964900.

It is not an unprimeable number, because it can be changed into a prime (21964937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24695 + ... + 25568.

It is an arithmetic number, because the mean of its divisors is an integer number (3015840).

Almost surely, 2^21964931 is an apocalyptic number.

21964931 is a deficient number, since it is larger than the sum of its proper divisors (2161789).

21964931 is a wasteful number, since it uses less digits than its factorization.

21964931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50305.

The product of its digits is 11664, while the sum is 35.

The square root of 21964931 is about 4686.6759008918. The cubic root of 21964931 is about 280.0549679498.

It can be divided in two parts, 21964 and 931, that multiplied together give a square (20448484 = 4522²).

The spelling of 21964931 in words is "twenty-one million, nine hundred sixty-four thousand, nine hundred thirty-one".