25123121316 has 18 divisors (see below), whose sum is σ = 63505667862. Its totient is φ = 8374373760.

The previous prime is 25123121299. The next prime is 25123121369. The reversal of 25123121316 is 61312132152.

25123121316 is a `hidden beast` number, since 2 + 512 + 3 + 12 + 131 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 13865062500 + 11258058816 = 117750^2 + 106104^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a self number, because there is not a number n which added to its sum of digits gives 25123121316.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 348932205 + ... + 348932276.

It is an arithmetic number, because the mean of its divisors is an integer number (3528092659).

Almost surely, 2^25123121316 is an apocalyptic number.

It is an amenable number.

25123121316 is an abundant number, since it is smaller than the sum of its proper divisors (38382546546).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25123121316 is a wasteful number, since it uses less digits than its factorization.

25123121316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 697864491 (or 697864486 counting only the distinct ones).

The product of its digits is 2160, while the sum is 27.

Adding to 25123121316 its reverse (61312132152), we get a palindrome (86435253468).

The spelling of 25123121316 in words is "twenty-five billion, one hundred twenty-three million, one hundred twenty-one thousand, three hundred sixteen".