28259291025 has 81 divisors (see below), whose sum is σ = 58916089713. Its totient is φ = 12910464000.

The previous prime is 28259291003. The next prime is 28259291101. The reversal of 28259291025 is 52019295282.

It is a happy number.

The square root of 28259291025 is 168105.

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

28259291025 is a `hidden beast` number, since 28 + 2 + 592 + 9 + 10 + 25 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 8839196289 + 19420094736 = 94017^2 + 139356^2 .

It is not a de Polignac number, because 28259291025 - 2²³ = 28250902417 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 17650225 + ... + 17651825.

Almost surely, 2^28259291025 is an apocalyptic number.

28259291025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

28259291025 is the 168105-th square number.

28259291025 is the 84053-rd centered octagonal number.

It is an amenable number.

28259291025 is an abundant number, since it is smaller than the sum of its proper divisors (30656798688).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28259291025 is an equidigital number, since it uses as much as digits as its factorization.

28259291025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3232 (or 1616 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 45.

The spelling of 28259291025 in words is "twenty-eight billion, two hundred fifty-nine million, two hundred ninety-one thousand, twenty-five".