28090931 has 8 divisors (see below), whose sum is σ = 30834624. Its totient is φ = 25378920.

The previous prime is 28090897. The next prime is 28090963. The reversal of 28090931 is 13909082.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28090931 - 2¹⁰ = 28089907 is a prime.

It is a super-2 number, since 2×28090931² = 1578200808893522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28090031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6041 + ... + 9626.

It is an arithmetic number, because the mean of its divisors is an integer number (3854328).

Almost surely, 2^28090931 is an apocalyptic number.

28090931 is a deficient number, since it is larger than the sum of its proper divisors (2743693).

28090931 is a wasteful number, since it uses less digits than its factorization.

28090931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15841.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 28090931 is about 5300.0878294609. The cubic root of 28090931 is about 303.9872563621.

The spelling of 28090931 in words is "twenty-eight million, ninety thousand, nine hundred thirty-one".