21463199557 has 2 divisors, whose sum is σ = 21463199558. Its totient is φ = 21463199556.

The previous prime is 21463199543. The next prime is 21463199581. The reversal of 21463199557 is 75599136412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14461024516 + 7002175041 = 120254^2 + 83679^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21463199557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21463199257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10731599778 + 10731599779.

It is an arithmetic number, because the mean of its divisors is an integer number (10731599779).

Almost surely, 2^21463199557 is an apocalyptic number.

It is an amenable number.

21463199557 is a deficient number, since it is larger than the sum of its proper divisors (1).

21463199557 is an equidigital number, since it uses as much as digits as its factorization.

21463199557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2041200, while the sum is 52.

The spelling of 21463199557 in words is "twenty-one billion, four hundred sixty-three million, one hundred ninety-nine thousand, five hundred fifty-seven".