27721992643 has 2 divisors, whose sum is σ = 27721992644. Its totient is φ = 27721992642.

The previous prime is 27721992619. The next prime is 27721992653. The reversal of 27721992643 is 34629912772.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27721992643 is a prime.

It is a super-2 number, since 2×27721992643² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (27721992653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13860996321 + 13860996322.

It is an arithmetic number, because the mean of its divisors is an integer number (13860996322).

Almost surely, 2^27721992643 is an apocalyptic number.

27721992643 is a deficient number, since it is larger than the sum of its proper divisors (1).

27721992643 is an equidigital number, since it uses as much as digits as its factorization.

27721992643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2286144, while the sum is 52.

The spelling of 27721992643 in words is "twenty-seven billion, seven hundred twenty-one million, nine hundred ninety-two thousand, six hundred forty-three".