28745973117 has 20 divisors (see below), whose sum is σ = 42946101660. Its totient is φ = 19161935424.

The previous prime is 28745973101. The next prime is 28745973119. The reversal of 28745973117 is 71137954782.

28745973117 is a `hidden beast` number, since 2 + 8 + 7 + 4 + 597 + 31 + 17 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 272448036 + 28473525081 = 16506^2 + 168741^2 .

It is not a de Polignac number, because 28745973117 - 2⁴ = 28745973101 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28745973119) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1357503 + ... + 1378515.

It is an arithmetic number, because the mean of its divisors is an integer number (2147305083).

Almost surely, 2^28745973117 is an apocalyptic number.

28745973117 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

28745973117 is a deficient number, since it is larger than the sum of its proper divisors (14200128543).

28745973117 is a wasteful number, since it uses less digits than its factorization.

28745973117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37914 (or 37905 counting only the distinct ones).

The product of its digits is 2963520, while the sum is 54.

The spelling of 28745973117 in words is "twenty-eight billion, seven hundred forty-five million, nine hundred seventy-three thousand, one hundred seventeen".