81080266 has 4 divisors (see below), whose sum is σ = 121620402. Its totient is φ = 40540132.

The previous prime is 81080231. The next prime is 81080273. The reversal of 81080266 is 66208018.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66208018 = 2 ⋅33104009.

It can be written as a sum of positive squares in only one way, i.e., 41024025 + 40056241 = 6405^2 + 6329^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20270065 + ... + 20270068.

Almost surely, 2^81080266 is an apocalyptic number.

81080266 is a deficient number, since it is larger than the sum of its proper divisors (40540136).

81080266 is a wasteful number, since it uses less digits than its factorization.

81080266 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40540135.

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 81080266 is about 9004.4581180657. The cubic root of 81080266 is about 432.8177419402.

The spelling of 81080266 in words is "eighty-one million, eighty thousand, two hundred sixty-six".