21102020099807 has 2 divisors, whose sum is σ = 21102020099808. Its totient is φ = 21102020099806.

The previous prime is 21102020099801. The next prime is 21102020100019. The reversal of 21102020099807 is 70899002020112.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21102020099807 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21102020099801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10551010049903 + 10551010049904.

It is an arithmetic number, because the mean of its divisors is an integer number (10551010049904).

Almost surely, 2^{21102020099807} is an apocalyptic number.

21102020099807 is a deficient number, since it is larger than the sum of its proper divisors (1).

21102020099807 is an equidigital number, since it uses as much as digits as its factorization.

21102020099807 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 41.

The spelling of 21102020099807 in words is "twenty-one trillion, one hundred two billion, twenty million, ninety-nine thousand, eight hundred seven".