81130368 has 64 divisors (see below), whose sum is σ = 235105920. Its totient is φ = 24583680.

The previous prime is 81130363. The next prime is 81130373. The reversal of 81130368 is 86303118.

It is an interprime number because it is at equal distance from previous prime (81130363) and next prime (81130373).

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×81130368² = 13164273223630848, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81130363) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5380 + ... + 13827.

It is an arithmetic number, because the mean of its divisors is an integer number (3673530).

Almost surely, 2^81130368 is an apocalyptic number.

81130368 is a gapful number since it is divisible by the number (88) formed by its first and last digit.

It is an amenable number.

81130368 is an abundant number, since it is smaller than the sum of its proper divisors (153975552).

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

81130368 is a wasteful number, since it uses less digits than its factorization.

81130368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19235 (or 19223 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 81130368 is about 9007.2397547750. The cubic root of 81130368 is about 432.9068740660.

The spelling of 81130368 in words is "eighty-one million, one hundred thirty thousand, three hundred sixty-eight".