28431018225 has 63 divisors (see below), whose sum is σ = 52899867633. Its totient is φ = 15151069440.

The previous prime is 28431018211. The next prime is 28431018233. The reversal of 28431018225 is 52281013482.

It is a happy number.

The square root of 28431018225 is 168615.

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

28431018225 is a `hidden beast` number, since 28 + 431 + 0 + 182 + 25 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1517959521 + 26913058704 = 38961^2 + 164052^2 .

It is not a de Polignac number, because 28431018225 - 2⁵ = 28431018193 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28431018225.

It is an unprimeable number.

It is a polite number, since it can be written in 62 ways as a sum of consecutive naturals, for example, 22762401 + ... + 22763649.

Almost surely, 2^28431018225 is an apocalyptic number.

28431018225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

28431018225 is the 168615-th square number.

28431018225 is the 84308-th centered octagonal number.

It is an amenable number.

28431018225 is a deficient number, since it is larger than the sum of its proper divisors (24468849408).

28431018225 is an frugal number, since it uses more digits than its factorization.

28431018225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2526 (or 1257 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

Multiplying 28431018225 by its sum of digits (36), we get a square (1023516656100 = 1011690²).

The spelling of 28431018225 in words is "twenty-eight billion, four hundred thirty-one million, eighteen thousand, two hundred twenty-five".