81888070 has 64 divisors (see below), whose sum is σ = 167795712. Its totient is φ = 28512000.

The previous prime is 81888061. The next prime is 81888071. The reversal of 81888070 is 7088818.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81888071) 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 31 ways as a sum of consecutive naturals, for example, 302035 + ... + 302305.

It is an arithmetic number, because the mean of its divisors is an integer number (2621808).

Almost surely, 2^81888070 is an apocalyptic number.

81888070 is an abundant number, since it is smaller than the sum of its proper divisors (85907642).

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

81888070 is a wasteful number, since it uses less digits than its factorization.

81888070 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 397.

The product of its (nonzero) digits is 28672, while the sum is 40.

The square root of 81888070 is about 9049.2027273125. The cubic root of 81888070 is about 434.2503846594.

It can be divided in two parts, 818 and 88070, that added together give a palindrome (88888).

The spelling of 81888070 in words is "eighty-one million, eight hundred eighty-eight thousand, seventy".