1999421 has 8 divisors (see below), whose sum is σ = 2129400. Its totient is φ = 1870848.

The previous prime is 1999379. The next prime is 1999423. The reversal of 1999421 is 1249991.

It can be written as a sum of positive squares in 4 ways, for example, as 532900 + 1466521 = 730^2 + 1211^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1999421 - 2¹⁰ = 1998397 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 (1999423) 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 7 ways as a sum of consecutive naturals, for example, 5555 + ... + 5903.

It is an arithmetic number, because the mean of its divisors is an integer number (266175).

2^1999421 is an apocalyptic number.

It is an amenable number.

1999421 is a deficient number, since it is larger than the sum of its proper divisors (129979).

1999421 is a wasteful number, since it uses less digits than its factorization.

1999421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 703.

The product of its digits is 5832, while the sum is 35.

The square root of 1999421 is about 1414.0088401421. The cubic root of 1999421 is about 125.9799455779.

The spelling of 1999421 in words is "one million, nine hundred ninety-nine thousand, four hundred twenty-one".