2661664161 has 8 divisors (see below), whose sum is σ = 3821876800. Its totient is φ = 1637947152.

The previous prime is 2661664141. The next prime is 2661664219. The reversal of 2661664161 is 1614661662.

It is a happy number.

2661664161 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 2661664161 - 2¹⁴ = 2661647777 is a prime.

It is a super-2 number, since 2×2661664161² = 14168912211903667842, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39), and also a Moran number because the ratio is a prime number: 68247799 = 2661664161 / (2 + 6 + 6 + 1 + 6 + 6 + 4 + 1 + 6 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2661664141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34123861 + ... + 34123938.

It is an arithmetic number, because the mean of its divisors is an integer number (477734600).

Almost surely, 2^2661664161 is an apocalyptic number.

It is an amenable number.

2661664161 is a deficient number, since it is larger than the sum of its proper divisors (1160212639).

2661664161 is a wasteful number, since it uses less digits than its factorization.

2661664161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68247815.

The product of its digits is 62208, while the sum is 39.

The square root of 2661664161 is about 51591.3186592473. The cubic root of 2661664161 is about 1385.8548699779.

The spelling of 2661664161 in words is "two billion, six hundred sixty-one million, six hundred sixty-four thousand, one hundred sixty-one".