219986561 has 4 divisors (see below), whose sum is σ = 220138800. Its totient is φ = 219834324.

The previous prime is 219986539. The next prime is 219986563. The reversal of 219986561 is 165689912.

It is a happy number.

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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-219986561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (219986563) 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, 73931 + ... + 76848.

It is an arithmetic number, because the mean of its divisors is an integer number (55034700).

Almost surely, 2^219986561 is an apocalyptic number.

It is an amenable number.

219986561 is a deficient number, since it is larger than the sum of its proper divisors (152239).

219986561 is a wasteful number, since it uses less digits than its factorization.

219986561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152238.

The product of its digits is 233280, while the sum is 47.

The square root of 219986561 is about 14831.9439386751. The cubic root of 219986561 is about 603.6687812023.

The spelling of 219986561 in words is "two hundred nineteen million, nine hundred eighty-six thousand, five hundred sixty-one".