1561435225 has 27 divisors (see below), whose sum is σ = 2254287357. Its totient is φ = 1069750080.

The previous prime is 1561435223. The next prime is 1561435231. The reversal of 1561435225 is 5225341651.

The square root of 1561435225 is 39515.

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 544335561 + 1017099664 = 23331^2 + 31892^2 .

It is not a de Polignac number, because 1561435225 - 2¹ = 1561435223 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1561435223) 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, 1382461 + ... + 1383589.

Almost surely, 2^1561435225 is an apocalyptic number.

1561435225 is the 39515-th square number.

1561435225 is the 19758-th centered octagonal number.

It is an amenable number.

1561435225 is a deficient number, since it is larger than the sum of its proper divisors (692852132).

1561435225 is an frugal number, since it uses more digits than its factorization.

1561435225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2282 (or 1141 counting only the distinct ones).

The product of its digits is 36000, while the sum is 34.

The cubic root of 1561435225 is about 1160.1335619596.

Adding to 1561435225 its reverse (5225341651), we get a palindrome (6786776876).

The spelling of 1561435225 in words is "one billion, five hundred sixty-one million, four hundred thirty-five thousand, two hundred twenty-five".