81383388 has 48 divisors (see below), whose sum is σ = 193616640. Its totient is φ = 26601984.

The previous prime is 81383383. The next prime is 81383389. The reversal of 81383388 is 88338318.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81383383) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 161545 + ... + 162047.

It is an arithmetic number, because the mean of its divisors is an integer number (4033680).

Almost surely, 2^81383388 is an apocalyptic number.

It is an amenable number.

81383388 is an abundant number, since it is smaller than the sum of its proper divisors (112233252).

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

81383388 is a wasteful number, since it uses less digits than its factorization.

81383388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 746 (or 744 counting only the distinct ones).

The product of its digits is 110592, while the sum is 42.

The square root of 81383388 is about 9021.2741893815. The cubic root of 81383388 is about 433.3564403194.

The spelling of 81383388 in words is "eighty-one million, three hundred eighty-three thousand, three hundred eighty-eight".