28191974 has 8 divisors (see below), whose sum is σ = 44126640. Its totient is φ = 13483096.

The previous prime is 28191971. The next prime is 28191979. The reversal of 28191974 is 47919182.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28191971) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 306389 + ... + 306480.

It is an arithmetic number, because the mean of its divisors is an integer number (5515830).

Almost surely, 2^28191974 is an apocalyptic number.

28191974 is a deficient number, since it is larger than the sum of its proper divisors (15934666).

28191974 is a wasteful number, since it uses less digits than its factorization.

28191974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 612894.

The product of its digits is 36288, while the sum is 41.

The square root of 28191974 is about 5309.6114735449. The cubic root of 28191974 is about 304.3513006578.

The spelling of 28191974 in words is "twenty-eight million, one hundred ninety-one thousand, nine hundred seventy-four".