1940921 has 4 divisors (see below), whose sum is σ = 1943844. Its totient is φ = 1938000.

The previous prime is 1940903. The next prime is 1940929. The reversal of 1940921 is 1290491.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 583696 + 1357225 = 764^2 + 1165^2 .

It is a cyclic number.

It is not a de Polignac number, because 1940921 - 2¹⁴ = 1924537 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1940929) 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, 71 + ... + 1971.

It is an arithmetic number, because the mean of its divisors is an integer number (485961).

2^1940921 is an apocalyptic number.

It is an amenable number.

1940921 is a deficient number, since it is larger than the sum of its proper divisors (2923).

1940921 is a wasteful number, since it uses less digits than its factorization.

1940921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2922.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 1940921 is about 1393.1694082200. The cubic root of 1940921 is about 124.7391038444.

The spelling of 1940921 in words is "one million, nine hundred forty thousand, nine hundred twenty-one".