2190866661 has 12 divisors (see below), whose sum is σ = 3176902092. Its totient is φ = 1454893056.

The previous prime is 2190866659. The next prime is 2190866669. The reversal of 2190866661 is 1666680912.

2190866661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 2153888100 + 36978561 = 46410^2 + 6081^2 .

It is not a de Polignac number, because 2190866661 - 2¹ = 2190866659 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2190866669) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 471286 + ... + 475911.

It is an arithmetic number, because the mean of its divisors is an integer number (264741841).

Almost surely, 2^2190866661 is an apocalyptic number.

It is an amenable number.

2190866661 is a deficient number, since it is larger than the sum of its proper divisors (986035431).

2190866661 is a wasteful number, since it uses less digits than its factorization.

2190866661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 947460 (or 947457 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 2190866661 is about 46806.6946173301. The cubic root of 2190866661 is about 1298.7891409615.

The spelling of 2190866661 in words is "two billion, one hundred ninety million, eight hundred sixty-six thousand, six hundred sixty-one".