81011455 has 16 divisors (see below), whose sum is σ = 113371200. Its totient is φ = 55549536.

The previous prime is 81011429. The next prime is 81011461. The reversal of 81011455 is 55411018.

It is a happy number.

It is not a de Polignac number, because 81011455 - 2⁷ = 81011327 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21904 + ... + 25333.

It is an arithmetic number, because the mean of its divisors is an integer number (7085700).

Almost surely, 2^81011455 is an apocalyptic number.

81011455 is a deficient number, since it is larger than the sum of its proper divisors (32359745).

81011455 is an equidigital number, since it uses as much as digits as its factorization.

81011455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47263 (or 47249 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 25.

The square root of 81011455 is about 9000.6363663910. The cubic root of 81011455 is about 432.6952663886.

The spelling of 81011455 in words is "eighty-one million, eleven thousand, four hundred fifty-five".