7851198861 has 30 divisors (see below), whose sum is σ = 12891490766. Its totient is φ = 4758296400.

The previous prime is 7851198851. The next prime is 7851198869. The reversal of 7851198861 is 1688911587.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 7850846025 + 352836 = 88605^2 + 594^2 .

It is not a de Polignac number, because 7851198861 - 2¹¹ = 7851196813 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 7851198798 and 7851198807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7851198869) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 390730 + ... + 410331.

Almost surely, 2^7851198861 is an apocalyptic number.

It is an amenable number.

7851198861 is a deficient number, since it is larger than the sum of its proper divisors (5040291905).

7851198861 is a wasteful number, since it uses less digits than its factorization.

7851198861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 801095 (or 801075 counting only the distinct ones).

The product of its digits is 967680, while the sum is 54.

The square root of 7851198861 is about 88606.9910390822. The cubic root of 7851198861 is about 1987.5222194739.

The spelling of 7851198861 in words is "seven billion, eight hundred fifty-one million, one hundred ninety-eight thousand, eight hundred sixty-one".