1899994 has 4 divisors (see below), whose sum is σ = 2849994. Its totient is φ = 949996.

The previous prime is 1899983. The next prime is 1900009. The reversal of 1899994 is 4999981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 4999981 = 7 ⋅714283.

It can be written as a sum of positive squares in only one way, i.e., 1428025 + 471969 = 1195^2 + 687^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 474997 + ... + 475000.

2^1899994 is an apocalyptic number.

1899994 is a deficient number, since it is larger than the sum of its proper divisors (950000).

1899994 is an equidigital number, since it uses as much as digits as its factorization.

1899994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 949999.

The product of its digits is 209952, while the sum is 49.

The square root of 1899994 is about 1378.4026987786. The cubic root of 1899994 is about 123.8561025879.

The spelling of 1899994 in words is "one million, eight hundred ninety-nine thousand, nine hundred ninety-four".