25912146721 has 4 divisors (see below), whose sum is σ = 26019666244. Its totient is φ = 25804627200.

The previous prime is 25912146719. The next prime is 25912146749. The reversal of 25912146721 is 12764121952.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20050560000 + 5861586721 = 141600^2 + 76561^2 .

It is a cyclic number.

It is not a de Polignac number, because 25912146721 - 2¹ = 25912146719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25912146761) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53759400 + ... + 53759881.

It is an arithmetic number, because the mean of its divisors is an integer number (6504916561).

Almost surely, 2^25912146721 is an apocalyptic number.

It is an amenable number.

25912146721 is a deficient number, since it is larger than the sum of its proper divisors (107519523).

25912146721 is a wasteful number, since it uses less digits than its factorization.

25912146721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107519522.

The product of its digits is 60480, while the sum is 40.

The spelling of 25912146721 in words is "twenty-five billion, nine hundred twelve million, one hundred forty-six thousand, seven hundred twenty-one".