21862986997 has 2 divisors, whose sum is σ = 21862986998. Its totient is φ = 21862986996.

The previous prime is 21862986989. The next prime is 21862987031. The reversal of 21862986997 is 79968926812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17847356836 + 4015630161 = 133594^2 + 63369^2 .

It is a cyclic number.

It is not a de Polignac number, because 21862986997 - 2³ = 21862986989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21862986947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10931493498 + 10931493499.

It is an arithmetic number, because the mean of its divisors is an integer number (10931493499).

Almost surely, 2^21862986997 is an apocalyptic number.

It is an amenable number.

21862986997 is a deficient number, since it is larger than the sum of its proper divisors (1).

21862986997 is an equidigital number, since it uses as much as digits as its factorization.

21862986997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 47029248, while the sum is 67.

The spelling of 21862986997 in words is "twenty-one billion, eight hundred sixty-two million, nine hundred eighty-six thousand, nine hundred ninety-seven".