28890031 has 2 divisors, whose sum is σ = 28890032. Its totient is φ = 28890030.

The previous prime is 28889989. The next prime is 28890053. The reversal of 28890031 is 13009882.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28890031 - 2²¹ = 26792879 is a prime.

It is a super-2 number, since 2×28890031² = 1669267782361922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28889975 and 28890002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28890091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14445015 + 14445016.

It is an arithmetic number, because the mean of its divisors is an integer number (14445016).

Almost surely, 2^28890031 is an apocalyptic number.

28890031 is a deficient number, since it is larger than the sum of its proper divisors (1).

28890031 is an equidigital number, since it uses as much as digits as its factorization.

28890031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 28890031 is about 5374.9447439020. The cubic root of 28890031 is about 306.8428462819.

The spelling of 28890031 in words is "twenty-eight million, eight hundred ninety thousand, thirty-one".