28020031 has 6 divisors (see below), whose sum is σ = 30341400. Its totient is φ = 25864488.

The previous prime is 28020023. The next prime is 28020043. The reversal of 28020031 is 13002082.

It is a happy number.

It is not a de Polignac number, because 28020031 - 2³ = 28020023 is a prime.

It is a super-2 number, since 2×28020031² = 1570244274481922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28019987 and 28020014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28020071) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 82731 + ... + 83068.

It is an arithmetic number, because the mean of its divisors is an integer number (5056900).

Almost surely, 2^28020031 is an apocalyptic number.

28020031 is a deficient number, since it is larger than the sum of its proper divisors (2321369).

28020031 is a wasteful number, since it uses less digits than its factorization.

28020031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165825 (or 165812 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 28020031 is about 5293.3950353247. The cubic root of 28020031 is about 303.7312917288.

The spelling of 28020031 in words is "twenty-eight million, twenty thousand, thirty-one".