21664483 has 2 divisors, whose sum is σ = 21664484. Its totient is φ = 21664482.

The previous prime is 21664471. The next prime is 21664501. The reversal of 21664483 is 38446612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21664483 - 2¹³ = 21656291 is a prime.

It is not a weakly prime, because it can be changed into another prime (21661483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10832241 + 10832242.

It is an arithmetic number, because the mean of its divisors is an integer number (10832242).

Almost surely, 2^21664483 is an apocalyptic number.

21664483 is a deficient number, since it is larger than the sum of its proper divisors (1).

21664483 is an equidigital number, since it uses as much as digits as its factorization.

21664483 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27648, while the sum is 34.

The square root of 21664483 is about 4654.5121119189. The cubic root of 21664483 is about 278.7721876338.

The spelling of 21664483 in words is "twenty-one million, six hundred sixty-four thousand, four hundred eighty-three".