216406045 has 4 divisors (see below), whose sum is σ = 259687260. Its totient is φ = 173124832.

The previous prime is 216406027. The next prime is 216406061. The reversal of 216406045 is 540604612.

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 64352484 + 152053561 = 8022^2 + 12331^2 .

It is a cyclic number.

It is not a de Polignac number, because 216406045 - 2⁵ = 216406013 is a prime.

It is a congruent number.

It is an unprimeable number.

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, 21640600 + ... + 21640609.

It is an arithmetic number, because the mean of its divisors is an integer number (64921815).

Almost surely, 2^216406045 is an apocalyptic number.

It is an amenable number.

216406045 is a deficient number, since it is larger than the sum of its proper divisors (43281215).

216406045 is an equidigital number, since it uses as much as digits as its factorization.

216406045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43281214.

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 216406045 is about 14710.7459022308. The cubic root of 216406045 is about 600.3757322523.

The spelling of 216406045 in words is "two hundred sixteen million, four hundred six thousand, forty-five".