7966389961 has 4 divisors (see below), whose sum is σ = 7966827972. Its totient is φ = 7965951952.

The previous prime is 7966389919. The next prime is 7966389979. The reversal of 7966389961 is 1699836697.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1699836697 = 13 ⋅130756669.

It can be written as a sum of positive squares in 2 ways, for example, as 3520167561 + 4446222400 = 59331^2 + 66680^2 .

It is a cyclic number.

It is not a de Polignac number, because 7966389961 - 2¹⁷ = 7966258889 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 7966389893 and 7966389902.

It is not an unprimeable number, because it can be changed into a prime (7966309961) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 190486 + ... + 228511.

It is an arithmetic number, because the mean of its divisors is an integer number (1991706993).

Almost surely, 2^7966389961 is an apocalyptic number.

It is an amenable number.

7966389961 is a deficient number, since it is larger than the sum of its proper divisors (438011).

7966389961 is a wasteful number, since it uses less digits than its factorization.

7966389961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438010.

The product of its digits is 26453952, while the sum is 64.

The square root of 7966389961 is about 89254.6355154734. The cubic root of 7966389961 is about 1997.1952318933.

The spelling of 7966389961 in words is "seven billion, nine hundred sixty-six million, three hundred eighty-nine thousand, nine hundred sixty-one".