3921649991 has 8 divisors (see below), whose sum is σ = 4487298720. Its totient is φ = 3357354528.

The previous prime is 3921649939. The next prime is 3921649999. The reversal of 3921649991 is 1999461293.

It is a happy number.

3921649991 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 3921649991 - 2²⁶ = 3854541127 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 (3921649999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 332096 + ... + 343701.

It is an arithmetic number, because the mean of its divisors is an integer number (560912340).

Almost surely, 2^3921649991 is an apocalyptic number.

3921649991 is a deficient number, since it is larger than the sum of its proper divisors (565648729).

3921649991 is an equidigital number, since it uses as much as digits as its factorization.

3921649991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 676633.

The product of its digits is 944784, while the sum is 53.

The square root of 3921649991 is about 62623.0787409881. The cubic root of 3921649991 is about 1576.9682276446.

The spelling of 3921649991 in words is "three billion, nine hundred twenty-one million, six hundred forty-nine thousand, nine hundred ninety-one".