7818621875 has 12 divisors (see below), whose sum is σ = 9772655760. Its totient is φ = 6254895000.

The previous prime is 7818621871. The next prime is 7818621887. The reversal of 7818621875 is 5781268187.

It is not a de Polignac number, because 7818621875 - 2² = 7818621871 is a prime.

It is a super-2 number, since 2×7818621875² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (7818621871) 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 11 ways as a sum of consecutive naturals, for example, 1247855 + ... + 1254104.

It is an arithmetic number, because the mean of its divisors is an integer number (814387980).

Almost surely, 2^7818621875 is an apocalyptic number.

7818621875 is a deficient number, since it is larger than the sum of its proper divisors (1954033885).

7818621875 is an frugal number, since it uses more digits than its factorization.

7818621875 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2501984 (or 2501964 counting only the distinct ones).

The product of its digits is 1505280, while the sum is 53.

The square root of 7818621875 is about 88422.9714214581. The cubic root of 7818621875 is about 1984.7694660862.

The spelling of 7818621875 in words is "seven billion, eight hundred eighteen million, six hundred twenty-one thousand, eight hundred seventy-five".