28597639 has 4 divisors (see below), whose sum is σ = 32683024. Its totient is φ = 24512256.

The previous prime is 28597631. The next prime is 28597643. The reversal of 28597639 is 93679582.

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 28597639 - 2³ = 28597631 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28597592 and 28597601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28597631) 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, 2042682 + ... + 2042695.

It is an arithmetic number, because the mean of its divisors is an integer number (8170756).

Almost surely, 2^28597639 is an apocalyptic number.

28597639 is a deficient number, since it is larger than the sum of its proper divisors (4085385).

28597639 is an equidigital number, since it uses as much as digits as its factorization.

28597639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4085384.

The product of its digits is 816480, while the sum is 49.

The square root of 28597639 is about 5347.6760373082. The cubic root of 28597639 is about 305.8041629296.

The spelling of 28597639 in words is "twenty-eight million, five hundred ninety-seven thousand, six hundred thirty-nine".