1999393287 has 4 divisors (see below), whose sum is σ = 2665857720. Its totient is φ = 1332928856.

The previous prime is 1999393283. The next prime is 1999393337. The reversal of 1999393287 is 7823939991.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1999393287 - 2² = 1999393283 is a prime.

It is a super-2 number, since 2×1999393287² = 7995147032201328738, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1999393287.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1999393283) 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, 333232212 + ... + 333232217.

It is an arithmetic number, because the mean of its divisors is an integer number (666464430).

Almost surely, 2^1999393287 is an apocalyptic number.

1999393287 is a deficient number, since it is larger than the sum of its proper divisors (666464433).

1999393287 is an equidigital number, since it uses as much as digits as its factorization.

1999393287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 666464432.

The product of its digits is 6613488, while the sum is 60.

The square root of 1999393287 is about 44714.5757779273. The cubic root of 1999393287 is about 1259.7936352633.

The spelling of 1999393287 in words is "one billion, nine hundred ninety-nine million, three hundred ninety-three thousand, two hundred eighty-seven".