1918021 has 12 divisors (see below), whose sum is σ = 2260576. Its totient is φ = 1594080.

The previous prime is 1918019. The next prime is 1918027. The reversal of 1918021 is 1208191.

It is not a de Polignac number, because 1918021 - 2¹ = 1918019 is a prime.

It is a hoax number, since the sum of its digits (22) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 1917983 and 1918001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1918027) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11686 + ... + 11848.

2^1918021 is an apocalyptic number.

It is an amenable number.

1918021 is a deficient number, since it is larger than the sum of its proper divisors (342555).

1918021 is an equidigital number, since it uses as much as digits as its factorization.

1918021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252 (or 211 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 22.

The square root of 1918021 is about 1384.9263518325. The cubic root of 1918021 is about 124.2465826891.

The spelling of 1918021 in words is "one million, nine hundred eighteen thousand, twenty-one".