28785117145 has 32 divisors (see below), whose sum is σ = 37027531296. Its totient is φ = 21405696000.

The previous prime is 28785117131. The next prime is 28785117169. The reversal of 28785117145 is 54171158782.

It can be written as a sum of positive squares in 16 ways, for example, as 6632962249 + 22152154896 = 81443^2 + 148836^2 .

It is not a de Polignac number, because 28785117145 - 2⁷ = 28785117017 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4292295 + ... + 4298995.

It is an arithmetic number, because the mean of its divisors is an integer number (1157110353).

Almost surely, 2^28785117145 is an apocalyptic number.

It is an amenable number.

28785117145 is a deficient number, since it is larger than the sum of its proper divisors (8242414151).

28785117145 is a wasteful number, since it uses less digits than its factorization.

28785117145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7341.

The product of its digits is 627200, while the sum is 49.

The spelling of 28785117145 in words is "twenty-eight billion, seven hundred eighty-five million, one hundred seventeen thousand, one hundred forty-five".