3951665648 has 20 divisors (see below), whose sum is σ = 8750117040. Its totient is φ = 1693570944.

The previous prime is 3951665647. The next prime is 3951665681. The reversal of 3951665648 is 8465661593.

It is a happy number.

3951665648 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×3951665648³ (a number of 30 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Smith number, since the sum of its digits (53) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 3951665648.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3951665647) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17641253 + ... + 17641476.

It is an arithmetic number, because the mean of its divisors is an integer number (437505852).

Almost surely, 2^3951665648 is an apocalyptic number.

It is an amenable number.

3951665648 is an abundant number, since it is smaller than the sum of its proper divisors (4798451392).

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

3951665648 is a wasteful number, since it uses less digits than its factorization.

3951665648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35282744 (or 35282738 counting only the distinct ones).

The product of its digits is 4665600, while the sum is 53.

The square root of 3951665648 is about 62862.2752372200. The cubic root of 3951665648 is about 1580.9812907600.

The spelling of 3951665648 in words is "three billion, nine hundred fifty-one million, six hundred sixty-five thousand, six hundred forty-eight".