28031975 has 12 divisors (see below), whose sum is σ = 35500704. Its totient is φ = 21947520.

The previous prime is 28031959. The next prime is 28031989. The reversal of 28031975 is 57913082.

28031975 = T₁₄₈₅ + T₁₄₈₆ + ... + T₁₅₀₉.

It is not a de Polignac number, because 28031975 - 2⁴ = 28031959 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10754 + ... + 13103.

It is an arithmetic number, because the mean of its divisors is an integer number (2958392).

Almost surely, 2^28031975 is an apocalyptic number.

28031975 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

28031975 is a deficient number, since it is larger than the sum of its proper divisors (7468729).

28031975 is a wasteful number, since it uses less digits than its factorization.

28031975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23914 (or 23909 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 28031975 is about 5294.5231135580. The cubic root of 28031975 is about 303.7744424211.

The spelling of 28031975 in words is "twenty-eight million, thirty-one thousand, nine hundred seventy-five".