1561740525 has 36 divisors (see below), whose sum is σ = 2799681300. Its totient is φ = 832204800.

The previous prime is 1561740497. The next prime is 1561740527. The reversal of 1561740525 is 5250471651.

1561740525 is a `hidden beast` number, since 1 + 5 + 61 + 74 + 0 + 525 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 8277129 + 1553463396 = 2877^2 + 39414^2 .

It is not a de Polignac number, because 1561740525 - 2⁸ = 1561740269 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1561740525.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561740527) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 346285 + ... + 350765.

It is an arithmetic number, because the mean of its divisors is an integer number (77768925).

Almost surely, 2^1561740525 is an apocalyptic number.

1561740525 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1561740525 is a deficient number, since it is larger than the sum of its proper divisors (1237940775).

1561740525 is a wasteful number, since it uses less digits than its factorization.

1561740525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6046 (or 6038 counting only the distinct ones).

The product of its (nonzero) digits is 42000, while the sum is 36.

The square root of 1561740525 is about 39518.8629011514. The cubic root of 1561740525 is about 1160.2091688306.

The spelling of 1561740525 in words is "one billion, five hundred sixty-one million, seven hundred forty thousand, five hundred twenty-five".