31872128 has 24 divisors (see below), whose sum is σ = 63622755. Its totient is φ = 15904128.

The previous prime is 31872121. The next prime is 31872149. The reversal of 31872128 is 82127813.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in only one way, i.e., 15936064 + 15936064 = 3992^2 + 3992^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=3992.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31872094 and 31872103.

It is not an unprimeable number, because it can be changed into a prime (31872121) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 63623 + ... + 64121.

Almost surely, 2^31872128 is an apocalyptic number.

It is an amenable number.

31872128 is a deficient number, since it is larger than the sum of its proper divisors (31750627).

31872128 is an frugal number, since it uses more digits than its factorization.

31872128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1012 (or 501 counting only the distinct ones).

The product of its digits is 5376, while the sum is 32.

The square root of 31872128 is about 5645.5405409934. The cubic root of 31872128 is about 317.0567622186.

Multiplying 31872128 by its sum of digits (32), we get a square (1019908096 = 31936²).

31872128 divided by its sum of digits (32) gives a square (996004 = 998²).

The spelling of 31872128 in words is "thirty-one million, eight hundred seventy-two thousand, one hundred twenty-eight".