821056319 has 4 divisors (see below), whose sum is σ = 840150696. Its totient is φ = 801961944.

The previous prime is 821056273. The next prime is 821056321. The reversal of 821056319 is 913650128.

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 821056319 - 2²⁰ = 820007743 is a prime.

It is a super-2 number, since 2×821056319² = 1348266957939659522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821056339) 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, 9547124 + ... + 9547209.

It is an arithmetic number, because the mean of its divisors is an integer number (210037674).

Almost surely, 2^821056319 is an apocalyptic number.

821056319 is a deficient number, since it is larger than the sum of its proper divisors (19094377).

821056319 is a wasteful number, since it uses less digits than its factorization.

821056319 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19094376.

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 821056319 is about 28654.0803202615. The cubic root of 821056319 is about 936.3919021305.

The spelling of 821056319 in words is "eight hundred twenty-one million, fifty-six thousand, three hundred nineteen".