25099412561 has 16 divisors (see below), whose sum is σ = 27742694400. Its totient is φ = 22586623488.

The previous prime is 25099412531. The next prime is 25099412573. The reversal of 25099412561 is 16521499052.

It is a cyclic number.

It is not a de Polignac number, because 25099412561 - 2¹⁴ = 25099396177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25099412501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1051325 + ... + 1074933.

It is an arithmetic number, because the mean of its divisors is an integer number (1733918400).

Almost surely, 2^25099412561 is an apocalyptic number.

It is an amenable number.

25099412561 is a deficient number, since it is larger than the sum of its proper divisors (2643281839).

25099412561 is a wasteful number, since it uses less digits than its factorization.

25099412561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26368.

The product of its (nonzero) digits is 194400, while the sum is 44.

The spelling of 25099412561 in words is "twenty-five billion, ninety-nine million, four hundred twelve thousand, five hundred sixty-one".