16400045 has 4 divisors (see below), whose sum is σ = 19680060. Its totient is φ = 13120032.

The previous prime is 16400017. The next prime is 16400047. The reversal of 16400045 is 54000461.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6584356 + 9815689 = 2566^2 + 3133^2 .

It is a cyclic number.

It is not a de Polignac number, because 16400045 - 2¹⁰ = 16399021 is a prime.

It is a super-2 number, since 2×16400045² = 537922952004050, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16400047) 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, 1640000 + ... + 1640009.

It is an arithmetic number, because the mean of its divisors is an integer number (4920015).

Almost surely, 2^16400045 is an apocalyptic number.

It is an amenable number.

16400045 is a deficient number, since it is larger than the sum of its proper divisors (3280015).

16400045 is an equidigital number, since it uses as much as digits as its factorization.

16400045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3280014.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 16400045 is about 4049.6969022385. The cubic root of 16400045 is about 254.0670509325.

It can be divided in two parts, 1 and 6400045, that added together give a palindrome (6400046).

The spelling of 16400045 in words is "sixteen million, four hundred thousand, forty-five".