28721497287 has 16 divisors (see below), whose sum is σ = 43770621440. Its totient is φ = 16410585312.

The previous prime is 28721497283. The next prime is 28721497309. The reversal of 28721497287 is 78279412782.

It is not a de Polignac number, because 28721497287 - 2² = 28721497283 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28721497283) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 153438 + ... + 284580.

It is an arithmetic number, because the mean of its divisors is an integer number (2735663840).

Almost surely, 2^28721497287 is an apocalyptic number.

28721497287 is a deficient number, since it is larger than the sum of its proper divisors (15049124153).

28721497287 is a wasteful number, since it uses less digits than its factorization.

28721497287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141582.

The product of its digits is 6322176, while the sum is 57.

The spelling of 28721497287 in words is "twenty-eight billion, seven hundred twenty-one million, four hundred ninety-seven thousand, two hundred eighty-seven".