81804269 has 2 divisors, whose sum is σ = 81804270. Its totient is φ = 81804268.

The previous prime is 81804251. The next prime is 81804287. The reversal of 81804269 is 96240818.

It is a balanced prime because it is at equal distance from previous prime (81804251) and next prime (81804287).

It can be written as a sum of positive squares in only one way, i.e., 81667369 + 136900 = 9037^2 + 370^2 .

It is a cyclic number.

It is not a de Polignac number, because 81804269 - 2²⁰ = 80755693 is a prime.

It is a super-2 number, since 2×81804269² = 13383876853248722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81804869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40902134 + 40902135.

It is an arithmetic number, because the mean of its divisors is an integer number (40902135).

Almost surely, 2^81804269 is an apocalyptic number.

It is an amenable number.

81804269 is a deficient number, since it is larger than the sum of its proper divisors (1).

81804269 is an equidigital number, since it uses as much as digits as its factorization.

81804269 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27648, while the sum is 38.

The square root of 81804269 is about 9044.5712446749. The cubic root of 81804269 is about 434.1022025651.

The spelling of 81804269 in words is "eighty-one million, eight hundred four thousand, two hundred sixty-nine".