820697239 has 2 divisors, whose sum is σ = 820697240. Its totient is φ = 820697238.

The previous prime is 820697197. The next prime is 820697243. The reversal of 820697239 is 932796028.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 820697239 - 2¹¹ = 820695191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (820697249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410348619 + 410348620.

It is an arithmetic number, because the mean of its divisors is an integer number (410348620).

Almost surely, 2^820697239 is an apocalyptic number.

820697239 is a deficient number, since it is larger than the sum of its proper divisors (1).

820697239 is an equidigital number, since it uses as much as digits as its factorization.

820697239 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 326592, while the sum is 46.

The square root of 820697239 is about 28647.8138607469. The cubic root of 820697239 is about 936.2553753072.

The spelling of 820697239 in words is "eight hundred twenty million, six hundred ninety-seven thousand, two hundred thirty-nine".