21735499 has 2 divisors, whose sum is σ = 21735500. Its totient is φ = 21735498.

The previous prime is 21735481. The next prime is 21735509. The reversal of 21735499 is 99453712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21735499 - 2²¹ = 19638347 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21735409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10867749 + 10867750.

It is an arithmetic number, because the mean of its divisors is an integer number (10867750).

Almost surely, 2^21735499 is an apocalyptic number.

21735499 is a deficient number, since it is larger than the sum of its proper divisors (1).

21735499 is an equidigital number, since it uses as much as digits as its factorization.

21735499 is an evil number, because the sum of its binary digits is even.

The product of its digits is 68040, while the sum is 40.

The square root of 21735499 is about 4662.1345969416. The cubic root of 21735499 is about 279.0764597336.

The spelling of 21735499 in words is "twenty-one million, seven hundred thirty-five thousand, four hundred ninety-nine".