1989401 has 2 divisors, whose sum is σ = 1989402. Its totient is φ = 1989400.

The previous prime is 1989353. The next prime is 1989413. The reversal of 1989401 is 1049891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1974025 + 15376 = 1405^2 + 124^2 .

It is an emirp because it is prime and its reverse (1049891) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1989401 is a prime.

It is a Sophie Germain prime.

It is an Ulam number.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1989101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 994700 + 994701.

It is an arithmetic number, because the mean of its divisors is an integer number (994701).

2^1989401 is an apocalyptic number.

It is an amenable number.

1989401 is a deficient number, since it is larger than the sum of its proper divisors (1).

1989401 is an equidigital number, since it uses as much as digits as its factorization.

1989401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 32.

The square root of 1989401 is about 1410.4612720667. The cubic root of 1989401 is about 125.7691456132.

The spelling of 1989401 in words is "one million, nine hundred eighty-nine thousand, four hundred one".