3991766400 has 384 divisors, whose sum is σ = 14934758400. Its totient is φ = 1040762880.

The previous prime is 3991766399. The next prime is 3991766417. The reversal of 3991766400 is 46671993.

3991766400 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (384).

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

It is a congruent number.

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, 4060309 + ... + 4061291.

It is an arithmetic number, because the mean of its divisors is an integer number (38892600).

Almost surely, 2^3991766400 is an apocalyptic number.

3991766400 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 3991766400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7467379200).

3991766400 is an abundant number, since it is smaller than the sum of its proper divisors (10942992000).

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

3991766400 is a wasteful number, since it uses less digits than its factorization.

3991766400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1063 (or 1040 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 45.

The square root of 3991766400 is about 63180.4273489821. The cubic root of 3991766400 is about 1586.3111350223.

The spelling of 3991766400 in words is "three billion, nine hundred ninety-one million, seven hundred sixty-six thousand, four hundred".