216723445 has 4 divisors (see below), whose sum is σ = 260068140. Its totient is φ = 173378752.

The previous prime is 216723431. The next prime is 216723469. The reversal of 216723445 is 544327612.

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 107039716 + 109683729 = 10346^2 + 10473^2 .

It is a cyclic number.

It is not a de Polignac number, because 216723445 - 2²³ = 208334837 is a prime.

It is a super-2 number, since 2×216723445² = 93938103225336050, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 216723445.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21672340 + ... + 21672349.

It is an arithmetic number, because the mean of its divisors is an integer number (65017035).

Almost surely, 2^216723445 is an apocalyptic number.

It is an amenable number.

216723445 is a deficient number, since it is larger than the sum of its proper divisors (43344695).

216723445 is an equidigital number, since it uses as much as digits as its factorization.

216723445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43344694.

The product of its digits is 40320, while the sum is 34.

The square root of 216723445 is about 14721.5299816289. The cubic root of 216723445 is about 600.6691100237.

The spelling of 216723445 in words is "two hundred sixteen million, seven hundred twenty-three thousand, four hundred forty-five".