25465553561 has 16 divisors (see below), whose sum is σ = 29372555904. Its totient is φ = 21626434944.

The previous prime is 25465553557. The next prime is 25465553587. The reversal of 25465553561 is 16535556452.

It is a cyclic number.

It is not a de Polignac number, because 25465553561 - 2² = 25465553557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25465553591) 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, 476171 + ... + 526943.

It is an arithmetic number, because the mean of its divisors is an integer number (1835784744).

Almost surely, 2^25465553561 is an apocalyptic number.

It is an amenable number.

25465553561 is a deficient number, since it is larger than the sum of its proper divisors (3907002343).

25465553561 is a wasteful number, since it uses less digits than its factorization.

25465553561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51440.

The product of its digits is 2700000, while the sum is 47.

The spelling of 25465553561 in words is "twenty-five billion, four hundred sixty-five million, five hundred fifty-three thousand, five hundred sixty-one".