3991065654 has 8 divisors (see below), whose sum is σ = 7982131320. Its totient is φ = 1330355216.

The previous prime is 3991065647. The next prime is 3991065697. The reversal of 3991065654 is 4565601993.

It is a happy number.

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

3991065654 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 332588799 + ... + 332588810.

It is an arithmetic number, because the mean of its divisors is an integer number (997766415).

Almost surely, 2^3991065654 is an apocalyptic number.

3991065654 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3991065654 is a wasteful number, since it uses less digits than its factorization.

3991065654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 665177614.

The product of its (nonzero) digits is 874800, while the sum is 48.

The square root of 3991065654 is about 63174.8815115628. The cubic root of 3991065654 is about 1586.2183050882.

The spelling of 3991065654 in words is "three billion, nine hundred ninety-one million, sixty-five thousand, six hundred fifty-four".