28128974 has 4 divisors (see below), whose sum is σ = 42193464. Its totient is φ = 14064486.

The previous prime is 28128973. The next prime is 28129007. The reversal of 28128974 is 47982182.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28128973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7032242 + ... + 7032245.

It is an arithmetic number, because the mean of its divisors is an integer number (10548366).

Almost surely, 2^28128974 is an apocalyptic number.

28128974 is a deficient number, since it is larger than the sum of its proper divisors (14064490).

28128974 is a wasteful number, since it uses less digits than its factorization.

28128974 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14064489.

The product of its digits is 64512, while the sum is 41.

The square root of 28128974 is about 5303.6755179781. The cubic root of 28128974 is about 304.1244224645.

The spelling of 28128974 in words is "twenty-eight million, one hundred twenty-eight thousand, nine hundred seventy-four".