21015012109999 has 2 divisors, whose sum is σ = 21015012110000. Its totient is φ = 21015012109998.

The previous prime is 21015012109933. The next prime is 21015012110063. The reversal of 21015012109999 is 99990121051012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21015012109999 - 2²¹ = 21015010012847 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21015012109099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10507506054999 + 10507506055000.

It is an arithmetic number, because the mean of its divisors is an integer number (10507506055000).

Almost surely, 2^{21015012109999} is an apocalyptic number.

21015012109999 is a deficient number, since it is larger than the sum of its proper divisors (1).

21015012109999 is an equidigital number, since it uses as much as digits as its factorization.

21015012109999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 131220, while the sum is 49.

The spelling of 21015012109999 in words is "twenty-one trillion, fifteen billion, twelve million, one hundred nine thousand, nine hundred ninety-nine".