820697779219 has 4 divisors (see below), whose sum is σ = 838159434144. Its totient is φ = 803236124296.

The previous prime is 820697779217. The next prime is 820697779273. The reversal of 820697779219 is 912977796028.

820697779219 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 820697779219 - 2¹ = 820697779217 is a prime.

It is a super-2 number, since 2×820697779219² (a number of 25 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (67) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (820697779217) 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, 8730827392 + ... + 8730827485.

It is an arithmetic number, because the mean of its divisors is an integer number (209539858536).

Almost surely, 2^820697779219 is an apocalyptic number.

820697779219 is a deficient number, since it is larger than the sum of its proper divisors (17461654925).

820697779219 is a wasteful number, since it uses less digits than its factorization.

820697779219 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17461654924.

The product of its (nonzero) digits is 48009024, while the sum is 67.

The spelling of 820697779219 in words is "eight hundred twenty billion, six hundred ninety-seven million, seven hundred seventy-nine thousand, two hundred nineteen".