81267500 has 30 divisors (see below), whose sum is σ = 177721236. Its totient is φ = 32506000.

The previous prime is 81267493. The next prime is 81267509. The reversal of 81267500 is 576218.

It is not an unprimeable number, because it can be changed into a prime (81267509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 13754 + ... + 18753.

Almost surely, 2^81267500 is an apocalyptic number.

It is an amenable number.

81267500 is an abundant number, since it is smaller than the sum of its proper divisors (96453736).

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

81267500 is a wasteful number, since it uses less digits than its factorization.

81267500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32531 (or 32514 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 29.

The square root of 81267500 is about 9014.8488617392. The cubic root of 81267500 is about 433.1506462010.

The spelling of 81267500 in words is "eighty-one million, two hundred sixty-seven thousand, five hundred".