81333180 has 48 divisors (see below), whose sum is σ = 253038240. Its totient is φ = 21688704.

The previous prime is 81333173. The next prime is 81333227. The reversal of 81333180 is 8133318.

It is a Harshad number since it is a multiple of its sum of digits (27).

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, 74769 + ... + 75848.

It is an arithmetic number, because the mean of its divisors is an integer number (5271630).

Almost surely, 2^81333180 is an apocalyptic number.

It is an amenable number.

81333180 is an abundant number, since it is smaller than the sum of its proper divisors (171705060).

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

81333180 is a wasteful number, since it uses less digits than its factorization.

81333180 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150635 (or 150627 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 81333180 is about 9018.4910045972. The cubic root of 81333180 is about 433.2673048639.

Adding to 81333180 its reverse (8133318), we get a palindrome (89466498).

The spelling of 81333180 in words is "eighty-one million, three hundred thirty-three thousand, one hundred eighty".