21000202100939 has 2 divisors, whose sum is σ = 21000202100940. Its totient is φ = 21000202100938.

The previous prime is 21000202100837. The next prime is 21000202101019. The reversal of 21000202100939 is 93900120200012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21000202100939 - 2¹² = 21000202096843 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (21000202100539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500101050469 + 10500101050470.

It is an arithmetic number, because the mean of its divisors is an integer number (10500101050470).

Almost surely, 2^{21000202100939} is an apocalyptic number.

21000202100939 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000202100939 is an equidigital number, since it uses as much as digits as its factorization.

21000202100939 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 29.

The spelling of 21000202100939 in words is "twenty-one trillion, two hundred two million, one hundred thousand, nine hundred thirty-nine".