6661993793 has 24 divisors (see below), whose sum is σ = 8482660200. Its totient is φ = 5184587520.

The previous prime is 6661993759. The next prime is 6661993801. The reversal of 6661993793 is 3973991666.

It can be written as a sum of positive squares in 4 ways, for example, as 4739329 + 6657254464 = 2177^2 + 81592^2 .

It is not a de Polignac number, because 6661993793 - 2²⁶ = 6594884929 is a prime.

It is a super-2 number, since 2×6661993793² = 88764322595941053698, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (6661993703) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 46868 + ... + 124581.

It is an arithmetic number, because the mean of its divisors is an integer number (353444175).

Almost surely, 2^6661993793 is an apocalyptic number.

It is an amenable number.

6661993793 is a deficient number, since it is larger than the sum of its proper divisors (1820666407).

6661993793 is a wasteful number, since it uses less digits than its factorization.

6661993793 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171537 (or 171530 counting only the distinct ones).

The product of its digits is 9920232, while the sum is 59.

The square root of 6661993793 is about 81621.0376863710. The cubic root of 6661993793 is about 1881.6322207330.

The spelling of 6661993793 in words is "six billion, six hundred sixty-one million, nine hundred ninety-three thousand, seven hundred ninety-three".