27989543651 has 4 divisors (see below), whose sum is σ = 27990787704. Its totient is φ = 27988299600.

The previous prime is 27989543629. The next prime is 27989543653. The reversal of 27989543651 is 15634598972.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 27989543651 - 2³⁴ = 10809674467 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27989543653) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 587645 + ... + 633486.

It is an arithmetic number, because the mean of its divisors is an integer number (6997696926).

Almost surely, 2^27989543651 is an apocalyptic number.

27989543651 is a deficient number, since it is larger than the sum of its proper divisors (1244053).

27989543651 is a wasteful number, since it uses less digits than its factorization.

27989543651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1244052.

The product of its digits is 16329600, while the sum is 59.

The spelling of 27989543651 in words is "twenty-seven billion, nine hundred eighty-nine million, five hundred forty-three thousand, six hundred fifty-one".