21885737 has 2 divisors, whose sum is σ = 21885738. Its totient is φ = 21885736.

The previous prime is 21885707. The next prime is 21885757. The reversal of 21885737 is 73758812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12082576 + 9803161 = 3476^2 + 3131^2 .

It is a cyclic number.

It is not a de Polignac number, because 21885737 - 2¹⁸ = 21623593 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21885694 and 21885703.

It is not a weakly prime, because it can be changed into another prime (21885707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10942868 + 10942869.

It is an arithmetic number, because the mean of its divisors is an integer number (10942869).

Almost surely, 2^21885737 is an apocalyptic number.

It is an amenable number.

21885737 is a deficient number, since it is larger than the sum of its proper divisors (1).

21885737 is an equidigital number, since it uses as much as digits as its factorization.

21885737 is an evil number, because the sum of its binary digits is even.

The product of its digits is 94080, while the sum is 41.

The square root of 21885737 is about 4678.2194262347. The cubic root of 21885737 is about 279.7179856099.

It can be divided in two parts, 21885 and 737, that added together give a palindrome (22622).

The spelling of 21885737 in words is "twenty-one million, eight hundred eighty-five thousand, seven hundred thirty-seven".