81224955 has 24 divisors (see below), whose sum is σ = 160903392. Its totient is φ = 37131264.

The previous prime is 81224921. The next prime is 81224993. The reversal of 81224955 is 55942218.

It is not a de Polignac number, because 81224955 - 2⁹ = 81224443 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 128614 + ... + 129243.

It is an arithmetic number, because the mean of its divisors is an integer number (6704308).

Almost surely, 2^81224955 is an apocalyptic number.

81224955 is a deficient number, since it is larger than the sum of its proper divisors (79678437).

81224955 is a wasteful number, since it uses less digits than its factorization.

81224955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257875 (or 257872 counting only the distinct ones).

The product of its digits is 28800, while the sum is 36.

The square root of 81224955 is about 9012.4888349445. The cubic root of 81224955 is about 433.0750456183.

It can be divided in two parts, 8122495 and 5, that added together give a square (8122500 = 2850²).

The spelling of 81224955 in words is "eighty-one million, two hundred twenty-four thousand, nine hundred fifty-five".