840878329 has 2 divisors, whose sum is σ = 840878330. Its totient is φ = 840878328.

The previous prime is 840878309. The next prime is 840878359. The reversal of 840878329 is 923878048.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 775511104 + 65367225 = 27848^2 + 8085^2 .

It is a cyclic number.

It is not a de Polignac number, because 840878329 - 2¹⁹ = 840354041 is a prime.

It is not a weakly prime, because it can be changed into another prime (840878309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 420439164 + 420439165.

It is an arithmetic number, because the mean of its divisors is an integer number (420439165).

Almost surely, 2^840878329 is an apocalyptic number.

It is an amenable number.

840878329 is a deficient number, since it is larger than the sum of its proper divisors (1).

840878329 is an equidigital number, since it uses as much as digits as its factorization.

840878329 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 774144, while the sum is 49.

The square root of 840878329 is about 28997.9021482589. The cubic root of 840878329 is about 943.8675455887.

It can be divided in two parts, 84087 and 8329, that added together give a square (92416 = 304²).

The spelling of 840878329 in words is "eight hundred forty million, eight hundred seventy-eight thousand, three hundred twenty-nine".