19400401 has 4 divisors (see below), whose sum is σ = 19409332. Its totient is φ = 19391472.

The previous prime is 19400377. The next prime is 19400411. The reversal of 19400401 is 10400491.

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 9759376 + 9641025 = 3124^2 + 3105^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19400401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19400411) 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, 1135 + ... + 6331.

It is an arithmetic number, because the mean of its divisors is an integer number (4852333).

Almost surely, 2^19400401 is an apocalyptic number.

It is an amenable number.

19400401 is a deficient number, since it is larger than the sum of its proper divisors (8931).

19400401 is an equidigital number, since it uses as much as digits as its factorization.

19400401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8930.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 19400401 is about 4404.5886300539. The cubic root of 19400401 is about 268.7015895496.

Adding to 19400401 its reverse (10400491), we get a palindrome (29800892).

The spelling of 19400401 in words is "nineteen million, four hundred thousand, four hundred one".