3999891456 has 320 divisors, whose sum is σ = 13131641160. Its totient is φ = 1203240960.

The previous prime is 3999891403. The next prime is 3999891463. The reversal of 3999891456 is 6541989993.

3999891456 is a `hidden beast` number, since 3 + 9 + 9 + 98 + 91 + 456 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 3999891393 and 3999891402.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 29196220 + ... + 29196356.

Almost surely, 2^3999891456 is an apocalyptic number.

3999891456 is a gapful number since it is divisible by the number (36) 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 3999891456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6565820580).

3999891456 is an abundant number, since it is smaller than the sum of its proper divisors (9131749704).

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

3999891456 is an equidigital number, since it uses as much as digits as its factorization.

3999891456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190 (or 153 counting only the distinct ones).

The product of its digits is 18895680, while the sum is 63.

The square root of 3999891456 is about 63244.6950818802. The cubic root of 3999891456 is about 1587.3866932667.

The spelling of 3999891456 in words is "three billion, nine hundred ninety-nine million, eight hundred ninety-one thousand, four hundred fifty-six".