25561519 has 2 divisors, whose sum is σ = 25561520. Its totient is φ = 25561518.

The previous prime is 25561511. The next prime is 25561541. The reversal of 25561519 is 91516552.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25561519 - 2³ = 25561511 is a prime.

It is a super-2 number, since 2×25561519² = 1306782507174722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25561511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12780759 + 12780760.

It is an arithmetic number, because the mean of its divisors is an integer number (12780760).

Almost surely, 2^25561519 is an apocalyptic number.

25561519 is a deficient number, since it is larger than the sum of its proper divisors (1).

25561519 is an equidigital number, since it uses as much as digits as its factorization.

25561519 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13500, while the sum is 34.

The square root of 25561519 is about 5055.8400884522. The cubic root of 25561519 is about 294.5747737375.

The spelling of 25561519 in words is "twenty-five million, five hundred sixty-one thousand, five hundred nineteen".