1995021 has 12 divisors (see below), whose sum is σ = 3293472. Its totient is φ = 1139976.

The previous prime is 1995013. The next prime is 1995023. The reversal of 1995021 is 1205991.

It is a happy number.

It is not a de Polignac number, because 1995021 - 2³ = 1995013 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1995023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15771 + ... + 15896.

It is an arithmetic number, because the mean of its divisors is an integer number (274456).

2^1995021 is an apocalyptic number.

It is an amenable number.

1995021 is a deficient number, since it is larger than the sum of its proper divisors (1298451).

1995021 is a wasteful number, since it uses less digits than its factorization.

1995021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31680 (or 31677 counting only the distinct ones).

The product of its (nonzero) digits is 810, while the sum is 27.

The square root of 1995021 is about 1412.4521230824. The cubic root of 1995021 is about 125.8874656597.

The spelling of 1995021 in words is "one million, nine hundred ninety-five thousand, twenty-one".