81276869 has 2 divisors, whose sum is σ = 81276870. Its totient is φ = 81276868.

The previous prime is 81276863. The next prime is 81276893. The reversal of 81276869 is 96867218.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68674369 + 12602500 = 8287^2 + 3550^2 .

It is a cyclic number.

It is not a de Polignac number, because 81276869 - 2¹² = 81272773 is a prime.

It is a super-2 number, since 2×81276869² = 13211858868886322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81276863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40638434 + 40638435.

It is an arithmetic number, because the mean of its divisors is an integer number (40638435).

Almost surely, 2^81276869 is an apocalyptic number.

It is an amenable number.

81276869 is a deficient number, since it is larger than the sum of its proper divisors (1).

81276869 is an equidigital number, since it uses as much as digits as its factorization.

81276869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 290304, while the sum is 47.

The square root of 81276869 is about 9015.3684894185. The cubic root of 81276869 is about 433.1672909542.

The spelling of 81276869 in words is "eighty-one million, two hundred seventy-six thousand, eight hundred sixty-nine".