820724819 has 2 divisors, whose sum is σ = 820724820. Its totient is φ = 820724818.

The previous prime is 820724813. The next prime is 820724843. The reversal of 820724819 is 918427028.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 820724819 - 2²⁰ = 819676243 is a prime.

It is a super-2 number, since 2×820724819² = 1347178457045165522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (820724813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410362409 + 410362410.

It is an arithmetic number, because the mean of its divisors is an integer number (410362410).

Almost surely, 2^820724819 is an apocalyptic number.

820724819 is a deficient number, since it is larger than the sum of its proper divisors (1).

820724819 is an equidigital number, since it uses as much as digits as its factorization.

820724819 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64512, while the sum is 41.

The square root of 820724819 is about 28648.2952197858. The cubic root of 820724819 is about 936.2658629888.

The spelling of 820724819 in words is "eight hundred twenty million, seven hundred twenty-four thousand, eight hundred nineteen".