28309472565 has 64 divisors (see below), whose sum is σ = 49788656640. Its totient is φ = 13621800960.

The previous prime is 28309472563. The next prime is 28309472599. The reversal of 28309472565 is 56527490382.

It is a happy number.

It is not a de Polignac number, because 28309472565 - 2¹ = 28309472563 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28309472563) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 17927946 + ... + 17929524.

It is an arithmetic number, because the mean of its divisors is an integer number (777947760).

Almost surely, 2^28309472565 is an apocalyptic number.

It is an amenable number.

28309472565 is a deficient number, since it is larger than the sum of its proper divisors (21479184075).

28309472565 is a wasteful number, since it uses less digits than its factorization.

28309472565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2354.

The product of its (nonzero) digits is 3628800, while the sum is 51.

The spelling of 28309472565 in words is "twenty-eight billion, three hundred nine million, four hundred seventy-two thousand, five hundred sixty-five".