28631089 has 4 divisors (see below), whose sum is σ = 28646500. Its totient is φ = 28615680.

The previous prime is 28631069. The next prime is 28631093. The reversal of 28631089 is 98013682.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12567025 + 16064064 = 3545^2 + 4008^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28631089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28631059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4464 + ... + 8785.

It is an arithmetic number, because the mean of its divisors is an integer number (7161625).

Almost surely, 2^28631089 is an apocalyptic number.

It is an amenable number.

28631089 is a deficient number, since it is larger than the sum of its proper divisors (15411).

28631089 is a wasteful number, since it uses less digits than its factorization.

28631089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15410.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 28631089 is about 5350.8026500704. The cubic root of 28631089 is about 305.9233471692.

It can be divided in two parts, 286 and 31089, that added together give a triangular number (31375 = T₂₅₀).

The spelling of 28631089 in words is "twenty-eight million, six hundred thirty-one thousand, eighty-nine".