816873553 has 2 divisors, whose sum is σ = 816873554. Its totient is φ = 816873552.

The previous prime is 816873527. The next prime is 816873571. The reversal of 816873553 is 355378618.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 486070209 + 330803344 = 22047^2 + 18188^2 .

It is a cyclic number.

It is not a de Polignac number, because 816873553 - 2⁵ = 816873521 is a prime.

It is not a weakly prime, because it can be changed into another prime (816873503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 408436776 + 408436777.

It is an arithmetic number, because the mean of its divisors is an integer number (408436777).

Almost surely, 2^816873553 is an apocalyptic number.

It is an amenable number.

816873553 is a deficient number, since it is larger than the sum of its proper divisors (1).

816873553 is an equidigital number, since it uses as much as digits as its factorization.

816873553 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 604800, while the sum is 46.

The square root of 816873553 is about 28580.9998600469. Note that the first 3 decimals coincide. The cubic root of 816873553 is about 934.7990848195.

The spelling of 816873553 in words is "eight hundred sixteen million, eight hundred seventy-three thousand, five hundred fifty-three".