1999445387 has 2 divisors, whose sum is σ = 1999445388. Its totient is φ = 1999445386.

The previous prime is 1999445369. The next prime is 1999445417. The reversal of 1999445387 is 7835449991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1999445387 - 2⁶ = 1999445323 is a prime.

It is not a weakly prime, because it can be changed into another prime (1999445587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 999722693 + 999722694.

It is an arithmetic number, because the mean of its divisors is an integer number (999722694).

Almost surely, 2^1999445387 is an apocalyptic number.

1999445387 is a deficient number, since it is larger than the sum of its proper divisors (1).

1999445387 is an equidigital number, since it uses as much as digits as its factorization.

1999445387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9797760, while the sum is 59.

The square root of 1999445387 is about 44715.1583582123. The cubic root of 1999445387 is about 1259.8045776958.

The spelling of 1999445387 in words is "one billion, nine hundred ninety-nine million, four hundred forty-five thousand, three hundred eighty-seven".