28172253081 has 8 divisors (see below), whose sum is σ = 42929147584. Its totient is φ = 16098430320.

The previous prime is 28172253071. The next prime is 28172253149. The reversal of 28172253081 is 18035227182.

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

It is not a de Polignac number, because 28172253081 - 2⁵ = 28172253049 is a prime.

It is a super-2 number, since 2×28172253081² (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 (28172253061) 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, 670767910 + ... + 670767951.

It is an arithmetic number, because the mean of its divisors is an integer number (5366143448).

Almost surely, 2^28172253081 is an apocalyptic number.

28172253081 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

28172253081 is a deficient number, since it is larger than the sum of its proper divisors (14756894503).

28172253081 is a wasteful number, since it uses less digits than its factorization.

28172253081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1341535871.

The product of its (nonzero) digits is 53760, while the sum is 39.

The spelling of 28172253081 in words is "twenty-eight billion, one hundred seventy-two million, two hundred fifty-three thousand, eighty-one".