21513511199 has 2 divisors, whose sum is σ = 21513511200. Its totient is φ = 21513511198.

The previous prime is 21513511189. The next prime is 21513511231. The reversal of 21513511199 is 99111531512.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21513511199 - 2⁴ = 21513511183 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21513511189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10756755599 + 10756755600.

It is an arithmetic number, because the mean of its divisors is an integer number (10756755600).

Almost surely, 2^21513511199 is an apocalyptic number.

21513511199 is a deficient number, since it is larger than the sum of its proper divisors (1).

21513511199 is an equidigital number, since it uses as much as digits as its factorization.

21513511199 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12150, while the sum is 38.

The spelling of 21513511199 in words is "twenty-one billion, five hundred thirteen million, five hundred eleven thousand, one hundred ninety-nine".