28056311491 has 8 divisors (see below), whose sum is σ = 30293383680. Its totient is φ = 25830509952.

The previous prime is 28056311489. The next prime is 28056311501. The reversal of 28056311491 is 19411365082.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28056311491 - 2¹ = 28056311489 is a prime.

It is a super-2 number, since 2×28056311491² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28056311441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2812486 + ... + 2822443.

It is an arithmetic number, because the mean of its divisors is an integer number (3786672960).

Almost surely, 2^28056311491 is an apocalyptic number.

28056311491 is a deficient number, since it is larger than the sum of its proper divisors (2237072189).

28056311491 is a wasteful number, since it uses less digits than its factorization.

28056311491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5635325.

The product of its (nonzero) digits is 51840, while the sum is 40.

The spelling of 28056311491 in words is "twenty-eight billion, fifty-six million, three hundred eleven thousand, four hundred ninety-one".