2662791661 has 4 divisors (see below), whose sum is σ = 2663206524. Its totient is φ = 2662376800.

The previous prime is 2662791647. The next prime is 2662791667. The reversal of 2662791661 is 1661972662.

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 1414512100 + 1248279561 = 37610^2 + 35331^2 .

It is a cyclic number.

It is not a de Polignac number, because 2662791661 - 2¹³ = 2662783469 is a prime.

It is a super-2 number, since 2×2662791661² = 14180918859782277842, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2662791667) 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, 197650 + ... + 210691.

It is an arithmetic number, because the mean of its divisors is an integer number (665801631).

Almost surely, 2^2662791661 is an apocalyptic number.

It is an amenable number.

2662791661 is a deficient number, since it is larger than the sum of its proper divisors (414863).

2662791661 is an equidigital number, since it uses as much as digits as its factorization.

2662791661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414862.

The product of its digits is 326592, while the sum is 46.

The square root of 2662791661 is about 51602.2447283062. The cubic root of 2662791661 is about 1386.0505283690.

The spelling of 2662791661 in words is "two billion, six hundred sixty-two million, seven hundred ninety-one thousand, six hundred sixty-one".