1995990 has 16 divisors (see below), whose sum is σ = 4790448. Its totient is φ = 532256.

The previous prime is 1995989. The next prime is 1995991. The reversal of 1995990 is 995991.

It is an interprime number because it is at equal distance from previous prime (1995989) and next prime (1995991).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1995991) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 33237 + ... + 33296.

It is an arithmetic number, because the mean of its divisors is an integer number (299403).

2^1995990 is an apocalyptic number.

1995990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1995990 is an abundant number, since it is smaller than the sum of its proper divisors (2794458).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1995990 is a wasteful number, since it uses less digits than its factorization.

1995990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66543.

The product of its (nonzero) digits is 32805, while the sum is 42.

The square root of 1995990 is about 1412.7951019168. The cubic root of 1995990 is about 125.9078439264.

Subtracting from 1995990 its reverse (995991), we obtain a palindrome (999999).

The spelling of 1995990 in words is "one million, nine hundred ninety-five thousand, nine hundred ninety".