216610445 has 4 divisors (see below), whose sum is σ = 259932540. Its totient is φ = 173288352.

The previous prime is 216610441. The next prime is 216610463. The reversal of 216610445 is 544016612.

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 37773316 + 178837129 = 6146^2 + 13373^2 .

It is a cyclic number.

It is not a de Polignac number, because 216610445 - 2² = 216610441 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216610441) 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, 21661040 + ... + 21661049.

It is an arithmetic number, because the mean of its divisors is an integer number (64983135).

Almost surely, 2^216610445 is an apocalyptic number.

It is an amenable number.

216610445 is a deficient number, since it is larger than the sum of its proper divisors (43322095).

216610445 is an equidigital number, since it uses as much as digits as its factorization.

216610445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43322094.

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 216610445 is about 14717.6915649160. The cubic root of 216610445 is about 600.5646952173.

The spelling of 216610445 in words is "two hundred sixteen million, six hundred ten thousand, four hundred forty-five".