3993434640 has 240 divisors, whose sum is σ = 15293114928. Its totient is φ = 925138944.

The previous prime is 3993434617. The next prime is 3993434671. The reversal of 3993434640 is 464343993.

It can be written as a sum of positive squares in 8 ways, for example, as 200845584 + 3792589056 = 14172^2 + 61584^2 .

It is a tau number, because it is divible by the number of its divisors (240).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 146572 + ... + 171668.

Almost surely, 2^3993434640 is an apocalyptic number.

3993434640 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3993434640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7646557464).

3993434640 is an abundant number, since it is smaller than the sum of its proper divisors (11299680288).

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

3993434640 is a wasteful number, since it uses less digits than its factorization.

3993434640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25146 (or 25137 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 45.

The square root of 3993434640 is about 63193.6281598074. The cubic root of 3993434640 is about 1586.5320880920.

The spelling of 3993434640 in words is "three billion, nine hundred ninety-three million, four hundred thirty-four thousand, six hundred forty".