1984021 has 4 divisors (see below), whose sum is σ = 2136652. Its totient is φ = 1831392.

The previous prime is 1984013. The next prime is 1984039. The reversal of 1984021 is 1204891.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1199025 + 784996 = 1095^2 + 886^2 .

It is a cyclic number.

It is not a de Polignac number, because 1984021 - 2³ = 1984013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1984061) 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, 76296 + ... + 76321.

It is an arithmetic number, because the mean of its divisors is an integer number (534163).

2^1984021 is an apocalyptic number.

It is an amenable number.

1984021 is a deficient number, since it is larger than the sum of its proper divisors (152631).

1984021 is a wasteful number, since it uses less digits than its factorization.

1984021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152630.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 1984021 is about 1408.5528034121. The cubic root of 1984021 is about 125.6556694341.

The spelling of 1984021 in words is "one million, nine hundred eighty-four thousand, twenty-one".