820537 has 2 divisors, whose sum is σ = 820538. Its totient is φ = 820536.

The previous prime is 820489. The next prime is 820541. The reversal of 820537 is 735028.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 571536 + 249001 = 756^2 + 499^2 .

It is a cyclic number.

It is not a de Polignac number, because 820537 - 2⁷ = 820409 is a prime.

It is not a weakly prime, because it can be changed into another prime (820577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410268 + 410269.

It is an arithmetic number, because the mean of its divisors is an integer number (410269).

2⁸²⁰⁵³⁷ is an apocalyptic number.

It is an amenable number.

820537 is a deficient number, since it is larger than the sum of its proper divisors (1).

820537 is an equidigital number, since it uses as much as digits as its factorization.

820537 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 820537 is about 905.8349739329. The cubic root of 820537 is about 93.6194437533.

The spelling of 820537 in words is "eight hundred twenty thousand, five hundred thirty-seven".