2661599644 has 24 divisors (see below), whose sum is σ = 5084610048. Its totient is φ = 1209014640.

The previous prime is 2661599621. The next prime is 2661599659. The reversal of 2661599644 is 4469951662.

2661599644 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×2661599644² = 14168225329881853472, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 2661599591 and 2661599600.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49647 + ... + 88249.

It is an arithmetic number, because the mean of its divisors is an integer number (211858752).

Almost surely, 2^2661599644 is an apocalyptic number.

It is an amenable number.

2661599644 is a deficient number, since it is larger than the sum of its proper divisors (2423010404).

2661599644 is a wasteful number, since it uses less digits than its factorization.

2661599644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40185 (or 40183 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 52.

The square root of 2661599644 is about 51590.6933855322. The cubic root of 2661599644 is about 1385.8436724819.

The spelling of 2661599644 in words is "two billion, six hundred sixty-one million, five hundred ninety-nine thousand, six hundred forty-four".