28258618609 has 27 divisors (see below), whose sum is σ = 31224878433. Its totient is φ = 25562414592.

The previous prime is 28258618589. The next prime is 28258618631. The reversal of 28258618609 is 90681685282.

It is a happy number.

The square root of 28258618609 is 168103.

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

It can be written as a sum of positive squares in 4 ways, for example, as 10659943009 + 17598675600 = 103247^2 + 132660^2 .

It is not a de Polignac number, because 28258618609 - 2¹⁹ = 28258094321 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28258618609.

It is not an unprimeable number, because it can be changed into a prime (28258618669) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 146417617 + ... + 146417809.

It is an arithmetic number, because the mean of its divisors is an integer number (1156476979).

Almost surely, 2^28258618609 is an apocalyptic number.

28258618609 is the 168103-rd square number.

28258618609 is the 84052-nd centered octagonal number.

It is an amenable number.

28258618609 is a deficient number, since it is larger than the sum of its proper divisors (2966259824).

28258618609 is an frugal number, since it uses more digits than its factorization.

28258618609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 546 (or 273 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 55.

The spelling of 28258618609 in words is "twenty-eight billion, two hundred fifty-eight million, six hundred eighteen thousand, six hundred nine".