28557617 has 4 divisors (see below), whose sum is σ = 31153776. Its totient is φ = 25961460.

The previous prime is 28557553. The next prime is 28557643. The reversal of 28557617 is 71675582.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28557617 - 2⁶ = 28557553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28557667) 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, 1298063 + ... + 1298084.

It is an arithmetic number, because the mean of its divisors is an integer number (7788444).

Almost surely, 2^28557617 is an apocalyptic number.

It is an amenable number.

28557617 is a deficient number, since it is larger than the sum of its proper divisors (2596159).

28557617 is a wasteful number, since it uses less digits than its factorization.

28557617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2596158.

The product of its digits is 117600, while the sum is 41.

The square root of 28557617 is about 5343.9327278700. The cubic root of 28557617 is about 305.6614400981.

The spelling of 28557617 in words is "twenty-eight million, five hundred fifty-seven thousand, six hundred seventeen".