219921228691 has 4 divisors (see below), whose sum is σ = 221526493272. Its totient is φ = 218315964112.

The previous prime is 219921228689. The next prime is 219921228721. The reversal of 219921228691 is 196822129912.

It is a happy number.

219921228691 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 219921228691 - 2¹ = 219921228689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (219921228661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 802632085 + ... + 802632358.

It is an arithmetic number, because the mean of its divisors is an integer number (55381623318).

Almost surely, 2^219921228691 is an apocalyptic number.

219921228691 is a deficient number, since it is larger than the sum of its proper divisors (1605264581).

219921228691 is a wasteful number, since it uses less digits than its factorization.

219921228691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1605264580.

The product of its digits is 559872, while the sum is 52.

The spelling of 219921228691 in words is "two hundred nineteen billion, nine hundred twenty-one million, two hundred twenty-eight thousand, six hundred ninety-one".