879721819 has 4 divisors (see below), whose sum is σ = 880369560. Its totient is φ = 879074080.

The previous prime is 879721783. The next prime is 879721847. The reversal of 879721819 is 918127978.

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 879721819 - 2⁹ = 879721307 is a prime.

It is a super-2 number, since 2×879721819² = 1547820957649337522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (879721519) 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, 321829 + ... + 324550.

It is an arithmetic number, because the mean of its divisors is an integer number (220092390).

Almost surely, 2^879721819 is an apocalyptic number.

879721819 is a deficient number, since it is larger than the sum of its proper divisors (647741).

879721819 is a wasteful number, since it uses less digits than its factorization.

879721819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 647740.

The product of its digits is 508032, while the sum is 52.

The square root of 879721819 is about 29660.1048379806. The cubic root of 879721819 is about 958.1829848641.

The spelling of 879721819 in words is "eight hundred seventy-nine million, seven hundred twenty-one thousand, eight hundred nineteen".