3261623661 has 12 divisors (see below), whose sum is σ = 4741244092. Its totient is φ = 2160565056.

The previous prime is 3261623633. The next prime is 3261623669. The reversal of 3261623661 is 1663261623.

3261623661 is a `hidden beast` number, since 3 + 2 + 616 + 2 + 36 + 6 + 1 = 666.

3261623661 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 1434061161 + 1827562500 = 37869^2 + 42750^2 .

It is not a de Polignac number, because 3261623661 - 2⁶ = 3261623597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3261623669) 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, 1152736 + ... + 1155561.

Almost surely, 2^3261623661 is an apocalyptic number.

It is an amenable number.

3261623661 is a deficient number, since it is larger than the sum of its proper divisors (1479620431).

3261623661 is a wasteful number, since it uses less digits than its factorization.

3261623661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2308460 (or 2308457 counting only the distinct ones).

The product of its digits is 46656, while the sum is 36.

The square root of 3261623661 is about 57110.6265155619. The cubic root of 3261623661 is about 1483.0118331238.

The spelling of 3261623661 in words is "three billion, two hundred sixty-one million, six hundred twenty-three thousand, six hundred sixty-one".