28589991935521 has 9 divisors (see below), whose sum is σ = 30174032227761. Its totient is φ = 27085159272564.

The previous prime is 28589991935507. The next prime is 28589991935567. The reversal of 28589991935521 is 12553919998582.

The square root of 28589991935521 is 5346961.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 28589991935521 - 2¹⁵ = 28589991902753 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28589991935221) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 101451550 + ... + 101732968.

It is an arithmetic number, because the mean of its divisors is an integer number (3352670247529).

Almost surely, 2^{28589991935521} is an apocalyptic number.

28589991935521 is the 5346961-st square number.

28589991935521 is the 2673481-st centered octagonal number.

It is an amenable number.

28589991935521 is a deficient number, since it is larger than the sum of its proper divisors (1584040292240).

28589991935521 is an frugal number, since it uses more digits than its factorization.

28589991935521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 562876 (or 281438 counting only the distinct ones).

The product of its digits is 629856000, while the sum is 76.

The spelling of 28589991935521 in words is "twenty-eight trillion, five hundred eighty-nine billion, nine hundred ninety-one million, nine hundred thirty-five thousand, five hundred twenty-one".