81817453 has 2 divisors, whose sum is σ = 81817454. Its totient is φ = 81817452.

The previous prime is 81817399. The next prime is 81817487. The reversal of 81817453 is 35471818.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45118089 + 36699364 = 6717^2 + 6058^2 .

It is a cyclic number.

It is not a de Polignac number, because 81817453 - 2⁹ = 81816941 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81817493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40908726 + 40908727.

It is an arithmetic number, because the mean of its divisors is an integer number (40908727).

Almost surely, 2^81817453 is an apocalyptic number.

It is an amenable number.

81817453 is a deficient number, since it is larger than the sum of its proper divisors (1).

81817453 is an equidigital number, since it uses as much as digits as its factorization.

81817453 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26880, while the sum is 37.

The square root of 81817453 is about 9045.3000503024. The cubic root of 81817453 is about 434.1255220327.

The spelling of 81817453 in words is "eighty-one million, eight hundred seventeen thousand, four hundred fifty-three".