21753540899 has 2 divisors, whose sum is σ = 21753540900. Its totient is φ = 21753540898.

The previous prime is 21753540877. The next prime is 21753540917. The reversal of 21753540899 is 99804535712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21753540899 - 2⁸ = 21753540643 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21753540899.

It is not a weakly prime, because it can be changed into another prime (21753540299) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10876770449 + 10876770450.

It is an arithmetic number, because the mean of its divisors is an integer number (10876770450).

Almost surely, 2^21753540899 is an apocalyptic number.

21753540899 is a deficient number, since it is larger than the sum of its proper divisors (1).

21753540899 is an equidigital number, since it uses as much as digits as its factorization.

21753540899 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2721600, while the sum is 53.

The spelling of 21753540899 in words is "twenty-one billion, seven hundred fifty-three million, five hundred forty thousand, eight hundred ninety-nine".