81224755800 has 48 divisors (see below), whose sum is σ = 251796744840. Its totient is φ = 21659934720.

The previous prime is 81224755757. The next prime is 81224755813. The reversal of 81224755800 is 855742218.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 67686697 + ... + 67687896.

Almost surely, 2^81224755800 is an apocalyptic number.

It is an amenable number.

81224755800 is an abundant number, since it is smaller than the sum of its proper divisors (170571989040).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81224755800 is a wasteful number, since it uses less digits than its factorization.

81224755800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135374612 (or 135374603 counting only the distinct ones).

The product of its (nonzero) digits is 179200, while the sum is 42.

The spelling of 81224755800 in words is "eighty-one billion, two hundred twenty-four million, seven hundred fifty-five thousand, eight hundred".