28697993571 has 32 divisors (see below), whose sum is σ = 42032934720. Its totient is φ = 17308569600.

The previous prime is 28697993551. The next prime is 28697993617. The reversal of 28697993571 is 17539979682.

It is not a de Polignac number, because 28697993571 - 2¹⁵ = 28697960803 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28697993551) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 647035 + ... + 689963.

It is an arithmetic number, because the mean of its divisors is an integer number (1313529210).

Almost surely, 2^28697993571 is an apocalyptic number.

28697993571 is a deficient number, since it is larger than the sum of its proper divisors (13334941149).

28697993571 is a wasteful number, since it uses less digits than its factorization.

28697993571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43287.

The product of its digits is 51438240, while the sum is 66.

The spelling of 28697993571 in words is "twenty-eight billion, six hundred ninety-seven million, nine hundred ninety-three thousand, five hundred seventy-one".