21857216299 has 2 divisors, whose sum is σ = 21857216300. Its totient is φ = 21857216298.

The previous prime is 21857216279. The next prime is 21857216341. The reversal of 21857216299 is 99261275812.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21857216299 is a prime.

It is not a weakly prime, because it can be changed into another prime (21857216279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10928608149 + 10928608150.

It is an arithmetic number, because the mean of its divisors is an integer number (10928608150).

Almost surely, 2^21857216299 is an apocalyptic number.

21857216299 is a deficient number, since it is larger than the sum of its proper divisors (1).

21857216299 is an equidigital number, since it uses as much as digits as its factorization.

21857216299 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1088640, while the sum is 52.

The spelling of 21857216299 in words is "twenty-one billion, eight hundred fifty-seven million, two hundred sixteen thousand, two hundred ninety-nine".