3940218661 has 8 divisors (see below), whose sum is σ = 4077168480. Its totient is φ = 3803340912.

The previous prime is 3940218649. The next prime is 3940218671. The reversal of 3940218661 is 1668120493.

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

It is a cyclic number.

It is not a de Polignac number, because 3940218661 - 2⁵ = 3940218629 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 (3940218631) 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, 108346 + ... + 140068.

It is an arithmetic number, because the mean of its divisors is an integer number (509646060).

Almost surely, 2^3940218661 is an apocalyptic number.

It is an amenable number.

3940218661 is a deficient number, since it is larger than the sum of its proper divisors (136949819).

3940218661 is a wasteful number, since it uses less digits than its factorization.

3940218661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36035.

The product of its (nonzero) digits is 62208, while the sum is 40.

The square root of 3940218661 is about 62771.1610614301. The cubic root of 3940218661 is about 1579.4532452310.

The spelling of 3940218661 in words is "three billion, nine hundred forty million, two hundred eighteen thousand, six hundred sixty-one".