28511971 has 8 divisors (see below), whose sum is σ = 29631488. Its totient is φ = 27405000.

The previous prime is 28511963. The next prime is 28511993. The reversal of 28511971 is 17911582.

It is a happy number.

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 28511971 - 2³ = 28511963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28511071) 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, 1636 + ... + 7726.

It is an arithmetic number, because the mean of its divisors is an integer number (3703936).

Almost surely, 2^28511971 is an apocalyptic number.

28511971 is a deficient number, since it is larger than the sum of its proper divisors (1119517).

28511971 is a wasteful number, since it uses less digits than its factorization.

28511971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6273.

The product of its digits is 5040, while the sum is 34.

The square root of 28511971 is about 5339.6601951810. The cubic root of 28511971 is about 305.4984986037.

The spelling of 28511971 in words is "twenty-eight million, five hundred eleven thousand, nine hundred seventy-one".