25737561 has 8 divisors (see below), whose sum is σ = 38129760. Its totient is φ = 17158356.

The previous prime is 25737559. The next prime is 25737563. The reversal of 25737561 is 16573752.

25737561 is a `hidden beast` number, since 25 + 73 + 7 + 561 = 666.

It is an interprime number because it is at equal distance from previous prime (25737559) and next prime (25737563).

It is not a de Polignac number, because 25737561 - 2¹ = 25737559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25737563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 476595 + ... + 476648.

It is an arithmetic number, because the mean of its divisors is an integer number (4766220).

Almost surely, 2^25737561 is an apocalyptic number.

It is an amenable number.

25737561 is a deficient number, since it is larger than the sum of its proper divisors (12392199).

25737561 is an equidigital number, since it uses as much as digits as its factorization.

25737561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 953252 (or 953246 counting only the distinct ones).

The product of its digits is 44100, while the sum is 36.

The square root of 25737561 is about 5073.2199834030. The cubic root of 25737561 is about 295.2494720113.

The spelling of 25737561 in words is "twenty-five million, seven hundred thirty-seven thousand, five hundred sixty-one".