561398040225 has 243 divisors, whose sum is σ = 1171381543059. Its totient is φ = 256788100800.

The previous prime is 561398040139. The next prime is 561398040323. The reversal of 561398040225 is 522040893165.

The square root of 561398040225 is 749265.

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

561398040225 is a `hidden beast` number, since 5 + 613 + 9 + 8 + 0 + 4 + 0 + 2 + 25 = 666.

It can be written as a sum of positive squares in only one way, i.e., 202103294481 + 359294745744 = 449559^2 + 599412^2 .

It is not a de Polignac number, because 561398040225 - 2²³ = 561389651617 is a prime.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 242 ways as a sum of consecutive naturals, for example, 2348945656 + ... + 2348945894.

Almost surely, 2^561398040225 is an apocalyptic number.

561398040225 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

561398040225 is the 749265-th square number.

561398040225 is the 374633-rd centered octagonal number.

It is an amenable number.

561398040225 is an abundant number, since it is smaller than the sum of its proper divisors (609983502834).

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

561398040225 is a wasteful number, since it uses less digits than its factorization.

561398040225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 554 (or 277 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

The spelling of 561398040225 in words is "five hundred sixty-one billion, three hundred ninety-eight million, forty thousand, two hundred twenty-five".