28251995779 has 16 divisors (see below), whose sum is σ = 33407467200. Its totient is φ = 23376697344.

The previous prime is 28251995777. The next prime is 28251995801. The reversal of 28251995779 is 97759915282.

It is a happy number.

It is not a de Polignac number, because 28251995779 - 2¹ = 28251995777 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28251995779.

It is not an unprimeable number, because it can be changed into a prime (28251995777) 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, 1617139 + ... + 1634515.

It is an arithmetic number, because the mean of its divisors is an integer number (2087966700).

Almost surely, 2^28251995779 is an apocalyptic number.

28251995779 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

28251995779 is a deficient number, since it is larger than the sum of its proper divisors (5155471421).

28251995779 is a wasteful number, since it uses less digits than its factorization.

28251995779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25422.

The product of its digits is 28576800, while the sum is 64.

The spelling of 28251995779 in words is "twenty-eight billion, two hundred fifty-one million, nine hundred ninety-five thousand, seven hundred seventy-nine".