1990099 has 4 divisors (see below), whose sum is σ = 2038680. Its totient is φ = 1941520.

The previous prime is 1990081. The next prime is 1990103. The reversal of 1990099 is 9900991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9900991 = 79 ⋅125329.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1990099 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1990039) 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, 24229 + ... + 24310.

It is an arithmetic number, because the mean of its divisors is an integer number (509670).

2^1990099 is an apocalyptic number.

1990099 is a deficient number, since it is larger than the sum of its proper divisors (48581).

1990099 is an equidigital number, since it uses as much as digits as its factorization.

1990099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48580.

The product of its (nonzero) digits is 6561, while the sum is 37.

The square root of 1990099 is about 1410.7086871498. The cubic root of 1990099 is about 125.7838529881.

The spelling of 1990099 in words is "one million, nine hundred ninety thousand, ninety-nine".