1995921 has 20 divisors (see below), whose sum is σ = 3059364. Its totient is φ = 1296000.

The previous prime is 1995913. The next prime is 1995937. The reversal of 1995921 is 1295991.

It can be written as a sum of positive squares in 2 ways, for example, as 810000 + 1185921 = 900^2 + 1089^2 .

It is not a de Polignac number, because 1995921 - 2³ = 1995913 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1995971) 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 19 ways as a sum of consecutive naturals, for example, 3021 + ... + 3621.

2^1995921 is an apocalyptic number.

It is an amenable number.

1995921 is a deficient number, since it is larger than the sum of its proper divisors (1063443).

1995921 is an equidigital number, since it uses as much as digits as its factorization.

1995921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 654 (or 645 counting only the distinct ones).

The product of its digits is 7290, while the sum is 36.

The square root of 1995921 is about 1412.7706820288. The cubic root of 1995921 is about 125.9063930605.

It can be divided in two parts, 1995 and 921, that added together give a square (2916 = 54²).

The spelling of 1995921 in words is "one million, nine hundred ninety-five thousand, nine hundred twenty-one".