3999999990 has 128 divisors (see below), whose sum is σ = 11260062720. Its totient is φ = 890523648.

The previous prime is 3999999979. The next prime is 4000000007. The reversal of 3999999990 is 999999993.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1398642 + ... + 1401498.

It is an arithmetic number, because the mean of its divisors is an integer number (87969240).

Almost surely, 2^3999999990 is an apocalyptic number.

3999999990 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 3999999990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5630031360).

3999999990 is an abundant number, since it is smaller than the sum of its proper divisors (7260062730).

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

3999999990 is a wasteful number, since it uses less digits than its factorization.

3999999990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3046.

The product of its (nonzero) digits is 129140163, while the sum is 75.

The square root of 3999999990 is about 63245.5531243106. The cubic root of 3999999990 is about 1587.4010506454.

The spelling of 3999999990 in words is "three billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety".