28025978 has 4 divisors (see below), whose sum is σ = 42038970. Its totient is φ = 14012988.

The previous prime is 28025951. The next prime is 28025989. The reversal of 28025978 is 87952082.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 19829209 + 8196769 = 4453^2 + 2863^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7006493 + ... + 7006496.

Almost surely, 2^28025978 is an apocalyptic number.

28025978 is a deficient number, since it is larger than the sum of its proper divisors (14012992).

28025978 is a wasteful number, since it uses less digits than its factorization.

28025978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14012991.

The product of its (nonzero) digits is 80640, while the sum is 41.

The square root of 28025978 is about 5293.9567433065. The cubic root of 28025978 is about 303.7527782886.

The spelling of 28025978 in words is "twenty-eight million, twenty-five thousand, nine hundred seventy-eight".