25552782721 has 2 divisors, whose sum is σ = 25552782722. Its totient is φ = 25552782720.

The previous prime is 25552782683. The next prime is 25552782727. The reversal of 25552782721 is 12728725552.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15902471025 + 9650311696 = 126105^2 + 98236^2 .

It is a cyclic number.

It is not a de Polignac number, because 25552782721 - 2²⁵ = 25519228289 is a prime.

It is not a weakly prime, because it can be changed into another prime (25552782727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12776391360 + 12776391361.

It is an arithmetic number, because the mean of its divisors is an integer number (12776391361).

Almost surely, 2^25552782721 is an apocalyptic number.

It is an amenable number.

25552782721 is a deficient number, since it is larger than the sum of its proper divisors (1).

25552782721 is an equidigital number, since it uses as much as digits as its factorization.

25552782721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 784000, while the sum is 46.

The spelling of 25552782721 in words is "twenty-five billion, five hundred fifty-two million, seven hundred eighty-two thousand, seven hundred twenty-one".