7881211994 has 8 divisors (see below), whose sum is σ = 11822249748. Its totient is φ = 3940462080.

The previous prime is 7881211981. The next prime is 7881212011. The reversal of 7881211994 is 4991121887.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 7690413025 + 190798969 = 87695^2 + 13813^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×7881211994² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19994 + ... + 127130.

Almost surely, 2^7881211994 is an apocalyptic number.

7881211994 is a deficient number, since it is larger than the sum of its proper divisors (3941037754).

7881211994 is a wasteful number, since it uses less digits than its factorization.

7881211994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143920.

The product of its digits is 290304, while the sum is 50.

The square root of 7881211994 is about 88776.1904679402. The cubic root of 7881211994 is about 1990.0515961808.

The spelling of 7881211994 in words is "seven billion, eight hundred eighty-one million, two hundred eleven thousand, nine hundred ninety-four".