7158943778561 has 4 divisors (see below), whose sum is σ = 7161404745300. Its totient is φ = 7156482811824.

The previous prime is 7158943778551. The next prime is 7158943778627. The reversal of 7158943778561 is 1658773498517.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6077408257600 + 1081535520961 = 2465240^2 + 1039969^2 .

It is a cyclic number.

It is not a de Polignac number, because 7158943778561 - 2¹⁴ = 7158943762177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7158943778551) 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, 1230479006 + ... + 1230484823.

It is an arithmetic number, because the mean of its divisors is an integer number (1790351186325).

Almost surely, 2^{7158943778561} is an apocalyptic number.

It is an amenable number.

7158943778561 is a deficient number, since it is larger than the sum of its proper divisors (2460966739).

7158943778561 is a wasteful number, since it uses less digits than its factorization.

7158943778561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2460966738.

The product of its digits is 355622400, while the sum is 71.

The spelling of 7158943778561 in words is "seven trillion, one hundred fifty-eight billion, nine hundred forty-three million, seven hundred seventy-eight thousand, five hundred sixty-one".