21200221019987 has 2 divisors, whose sum is σ = 21200221019988. Its totient is φ = 21200221019986.

The previous prime is 21200221019921. The next prime is 21200221020047. The reversal of 21200221019987 is 78991012200212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21200221019987 - 2²⁴ = 21200204242771 is a prime.

It is not a weakly prime, because it can be changed into another prime (21200221010987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600110509993 + 10600110509994.

It is an arithmetic number, because the mean of its divisors is an integer number (10600110509994).

Almost surely, 2^{21200221019987} is an apocalyptic number.

21200221019987 is a deficient number, since it is larger than the sum of its proper divisors (1).

21200221019987 is an equidigital number, since it uses as much as digits as its factorization.

21200221019987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72576, while the sum is 44.

The spelling of 21200221019987 in words is "twenty-one trillion, two hundred billion, two hundred twenty-one million, nineteen thousand, nine hundred eighty-seven".