1999445380 has 12 divisors (see below), whose sum is σ = 4198835340. Its totient is φ = 799778144.

The previous prime is 1999445369. The next prime is 1999445387. The reversal of 1999445380 is 835449991.

It can be written as a sum of positive squares in 2 ways, for example, as 1085834304 + 913611076 = 32952^2 + 30226^2 .

It is not an unprimeable number, because it can be changed into a prime (1999445387) 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, 49986115 + ... + 49986154.

It is an arithmetic number, because the mean of its divisors is an integer number (349902945).

Almost surely, 2^1999445380 is an apocalyptic number.

1999445380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1999445380 is an abundant number, since it is smaller than the sum of its proper divisors (2199389960).

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

1999445380 is a wasteful number, since it uses less digits than its factorization.

1999445380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99972278 (or 99972276 counting only the distinct ones).

The product of its (nonzero) digits is 1399680, while the sum is 52.

The square root of 1999445380 is about 44715.1582799390. The cubic root of 1999445380 is about 1259.8045762257.

The spelling of 1999445380 in words is "one billion, nine hundred ninety-nine million, four hundred forty-five thousand, three hundred eighty".