28569961 has 4 divisors (see below), whose sum is σ = 32651392. Its totient is φ = 24488532.

The previous prime is 28569943. The next prime is 28569973. The reversal of 28569961 is 16996582.

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 28569961 - 2⁵ = 28569929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28569161) 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, 2040705 + ... + 2040718.

It is an arithmetic number, because the mean of its divisors is an integer number (8162848).

Almost surely, 2^28569961 is an apocalyptic number.

It is an amenable number.

28569961 is a deficient number, since it is larger than the sum of its proper divisors (4081431).

28569961 is an equidigital number, since it uses as much as digits as its factorization.

28569961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4081430.

The product of its digits is 233280, while the sum is 46.

The square root of 28569961 is about 5345.0875577487. The cubic root of 28569961 is about 305.7054743664.

The spelling of 28569961 in words is "twenty-eight million, five hundred sixty-nine thousand, nine hundred sixty-one".