25251216516 has 72 divisors (see below), whose sum is σ = 66147681600. Its totient is φ = 8112404160.

The previous prime is 25251216511. The next prime is 25251216521. The reversal of 25251216516 is 61561215252.

25251216516 is a `hidden beast` number, since 2 + 525 + 121 + 6 + 5 + 1 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (25251216511) and next prime (25251216521).

It is a super-2 number, since 2×25251216516² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (25251216511) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 574945 + ... + 617303.

It is an arithmetic number, because the mean of its divisors is an integer number (918717800).

Almost surely, 2^25251216516 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25251216516, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33073840800).

25251216516 is an abundant number, since it is smaller than the sum of its proper divisors (40896465084).

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

25251216516 is a wasteful number, since it uses less digits than its factorization.

25251216516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42969 (or 42964 counting only the distinct ones).

The product of its digits is 36000, while the sum is 36.

The spelling of 25251216516 in words is "twenty-five billion, two hundred fifty-one million, two hundred sixteen thousand, five hundred sixteen".