7861218725 has 6 divisors (see below), whose sum is σ = 9747911250. Its totient is φ = 6288974960.

The previous prime is 7861218721. The next prime is 7861218773. The reversal of 7861218725 is 5278121687.

It can be written as a sum of positive squares in 3 ways, for example, as 289782529 + 7571436196 = 17023^2 + 87014^2 .

It is not a de Polignac number, because 7861218725 - 2² = 7861218721 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 7861218725.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7861218721) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 157224350 + ... + 157224399.

It is an arithmetic number, because the mean of its divisors is an integer number (1624651875).

Almost surely, 2^7861218725 is an apocalyptic number.

It is an amenable number.

7861218725 is a deficient number, since it is larger than the sum of its proper divisors (1886692525).

7861218725 is a wasteful number, since it uses less digits than its factorization.

7861218725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314448759 (or 314448754 counting only the distinct ones).

The product of its digits is 376320, while the sum is 47.

The square root of 7861218725 is about 88663.5140573618. The cubic root of 7861218725 is about 1988.3673658368.

The spelling of 7861218725 in words is "seven billion, eight hundred sixty-one million, two hundred eighteen thousand, seven hundred twenty-five".