1999742 has 8 divisors (see below), whose sum is σ = 3023616. Its totient is φ = 991872.

The previous prime is 1999733. The next prime is 1999771. The reversal of 1999742 is 2479991.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 1999742.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3683 + ... + 4190.

It is an arithmetic number, because the mean of its divisors is an integer number (377952).

2^1999742 is an apocalyptic number.

1999742 is a deficient number, since it is larger than the sum of its proper divisors (1023874).

1999742 is a wasteful number, since it uses less digits than its factorization.

1999742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8002.

The product of its digits is 40824, while the sum is 41.

The square root of 1999742 is about 1414.1223426564. The cubic root of 1999742 is about 125.9866870960.

Subtracting 1999742 from its reverse (2479991), we obtain a square (480249 = 693²).

The spelling of 1999742 in words is "one million, nine hundred ninety-nine thousand, seven hundred forty-two".