820973626609 has 2 divisors, whose sum is σ = 820973626610. Its totient is φ = 820973626608.

The previous prime is 820973626601. The next prime is 820973626639. The reversal of 820973626609 is 906626379028.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 817029786609 + 3943840000 = 903897^2 + 62800^2 .

It is a cyclic number.

It is not a de Polignac number, because 820973626609 - 2³ = 820973626601 is a prime.

It is not a weakly prime, because it can be changed into another prime (820973626601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410486813304 + 410486813305.

It is an arithmetic number, because the mean of its divisors is an integer number (410486813305).

Almost surely, 2^820973626609 is an apocalyptic number.

It is an amenable number.

820973626609 is a deficient number, since it is larger than the sum of its proper divisors (1).

820973626609 is an equidigital number, since it uses as much as digits as its factorization.

820973626609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11757312, while the sum is 58.

The spelling of 820973626609 in words is "eight hundred twenty billion, nine hundred seventy-three million, six hundred twenty-six thousand, six hundred nine".