820756879 has 2 divisors, whose sum is σ = 820756880. Its totient is φ = 820756878.

The previous prime is 820756799. The next prime is 820756913. The reversal of 820756879 is 978657028.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 820756879 - 2¹⁹ = 820232591 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (820757879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410378439 + 410378440.

It is an arithmetic number, because the mean of its divisors is an integer number (410378440).

Almost surely, 2^820756879 is an apocalyptic number.

820756879 is a deficient number, since it is larger than the sum of its proper divisors (1).

820756879 is an equidigital number, since it uses as much as digits as its factorization.

820756879 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1693440, while the sum is 52.

The square root of 820756879 is about 28648.8547589603. The cubic root of 820756879 is about 936.2780539579.

The spelling of 820756879 in words is "eight hundred twenty million, seven hundred fifty-six thousand, eight hundred seventy-nine".