21877948597 has 2 divisors, whose sum is σ = 21877948598. Its totient is φ = 21877948596.

The previous prime is 21877948537. The next prime is 21877948709. The reversal of 21877948597 is 79584977812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19948455121 + 1929493476 = 141239^2 + 43926^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21877948597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21877948537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10938974298 + 10938974299.

It is an arithmetic number, because the mean of its divisors is an integer number (10938974299).

Almost surely, 2^21877948597 is an apocalyptic number.

It is an amenable number.

21877948597 is a deficient number, since it is larger than the sum of its proper divisors (1).

21877948597 is an equidigital number, since it uses as much as digits as its factorization.

21877948597 is an evil number, because the sum of its binary digits is even.

The product of its digits is 71124480, while the sum is 67.

The spelling of 21877948597 in words is "twenty-one billion, eight hundred seventy-seven million, nine hundred forty-eight thousand, five hundred ninety-seven".