21322019987 has 2 divisors, whose sum is σ = 21322019988. Its totient is φ = 21322019986.

The previous prime is 21322019959. The next prime is 21322020053. The reversal of 21322019987 is 78991022312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21322019987 - 2¹⁴ = 21322003603 is a prime.

It is not a weakly prime, because it can be changed into another prime (21322019287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10661009993 + 10661009994.

It is an arithmetic number, because the mean of its divisors is an integer number (10661009994).

Almost surely, 2^21322019987 is an apocalyptic number.

21322019987 is a deficient number, since it is larger than the sum of its proper divisors (1).

21322019987 is an equidigital number, since it uses as much as digits as its factorization.

21322019987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108864, while the sum is 44.

The spelling of 21322019987 in words is "twenty-one billion, three hundred twenty-two million, nineteen thousand, nine hundred eighty-seven".