28870651 has 4 divisors (see below), whose sum is σ = 28892232. Its totient is φ = 28849072.

The previous prime is 28870649. The next prime is 28870661. The reversal of 28870651 is 15607882.

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

It is a cyclic number.

It is not a de Polignac number, because 28870651 - 2¹ = 28870649 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28870651.

It is not an unprimeable number, because it can be changed into a prime (28870661) 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, 8641 + ... + 11506.

It is an arithmetic number, because the mean of its divisors is an integer number (7223058).

Almost surely, 2^28870651 is an apocalyptic number.

28870651 is a deficient number, since it is larger than the sum of its proper divisors (21581).

28870651 is a wasteful number, since it uses less digits than its factorization.

28870651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21580.

The product of its (nonzero) digits is 26880, while the sum is 37.

The square root of 28870651 is about 5373.1416322297. The cubic root of 28870651 is about 306.7742188656.

The spelling of 28870651 in words is "twenty-eight million, eight hundred seventy thousand, six hundred fifty-one".