4445618661 has 24 divisors (see below), whose sum is σ = 7264674144. Its totient is φ = 2694312720.

The previous prime is 4445618629. The next prime is 4445618669. The reversal of 4445618661 is 1668165444.

4445618661 is a `hidden beast` number, since 4 + 4 + 4 + 561 + 86 + 6 + 1 = 666.

It is not a de Polignac number, because 4445618661 - 2⁵ = 4445618629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4445618669) 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, 828906 + ... + 834251.

It is an arithmetic number, because the mean of its divisors is an integer number (302694756).

Almost surely, 2^4445618661 is an apocalyptic number.

It is an amenable number.

4445618661 is a deficient number, since it is larger than the sum of its proper divisors (2819055483).

4445618661 is a wasteful number, since it uses less digits than its factorization.

4445618661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1663183 (or 1663171 counting only the distinct ones).

The product of its digits is 552960, while the sum is 45.

The square root of 4445618661 is about 66675.4727092354. The cubic root of 4445618661 is about 1644.2861634898.

The spelling of 4445618661 in words is "four billion, four hundred forty-five million, six hundred eighteen thousand, six hundred sixty-one".