81227755 has 16 divisors (see below), whose sum is σ = 117262080. Its totient is φ = 52767072.

The previous prime is 81227749. The next prime is 81227767. The reversal of 81227755 is 55772218.

It is a cyclic number.

It is not a de Polignac number, because 81227755 - 2⁵ = 81227723 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 60409 + ... + 61738.

It is an arithmetic number, because the mean of its divisors is an integer number (7328880).

Almost surely, 2^81227755 is an apocalyptic number.

81227755 is a deficient number, since it is larger than the sum of its proper divisors (36034325).

81227755 is a wasteful number, since it uses less digits than its factorization.

81227755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122178.

The product of its digits is 39200, while the sum is 37.

The square root of 81227755 is about 9012.6441736041. The cubic root of 81227755 is about 433.0800219059.

The spelling of 81227755 in words is "eighty-one million, two hundred twenty-seven thousand, seven hundred fifty-five".