831878609 has 2 divisors, whose sum is σ = 831878610. Its totient is φ = 831878608.

The previous prime is 831878599. The next prime is 831878617. The reversal of 831878609 is 906878138.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 682672384 + 149206225 = 26128^2 + 12215^2 .

It is a cyclic number.

It is not a de Polignac number, because 831878609 - 2¹² = 831874513 is a prime.

It is a super-2 number, since 2×831878609² = 1384044040223549762, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (831878809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 415939304 + 415939305.

It is an arithmetic number, because the mean of its divisors is an integer number (415939305).

Almost surely, 2^831878609 is an apocalyptic number.

It is an amenable number.

831878609 is a deficient number, since it is larger than the sum of its proper divisors (1).

831878609 is an equidigital number, since it uses as much as digits as its factorization.

831878609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 580608, while the sum is 50.

The square root of 831878609 is about 28842.3058890928. The cubic root of 831878609 is about 940.4881307370.

The spelling of 831878609 in words is "eight hundred thirty-one million, eight hundred seventy-eight thousand, six hundred nine".