16400001 has 4 divisors (see below), whose sum is σ = 21866672. Its totient is φ = 10933332.

The previous prime is 16399987. The next prime is 16400017. The reversal of 16400001 is 10000461.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 16400001 - 2⁶ = 16399937 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 16400001.

It is not an unprimeable number, because it can be changed into a prime (16400101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2733331 + ... + 2733336.

It is an arithmetic number, because the mean of its divisors is an integer number (5466668).

Almost surely, 2^16400001 is an apocalyptic number.

It is an amenable number.

16400001 is a deficient number, since it is larger than the sum of its proper divisors (5466671).

16400001 is an equidigital number, since it uses as much as digits as its factorization.

16400001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5466670.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 16400001 is about 4049.6914697295. The cubic root of 16400001 is about 254.0668237185.

Adding to 16400001 its reverse (10000461), we get a palindrome (26400462).

The spelling of 16400001 in words is "sixteen million, four hundred thousand, one".