81878526 has 40 divisors (see below), whose sum is σ = 183985824. Its totient is φ = 27216000.

The previous prime is 81878509. The next prime is 81878527. The reversal of 81878526 is 62587818.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81878527) 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 19 ways as a sum of consecutive naturals, for example, 108651 + ... + 109401.

Almost surely, 2^81878526 is an apocalyptic number.

81878526 is an abundant number, since it is smaller than the sum of its proper divisors (102107298).

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

81878526 is a wasteful number, since it uses less digits than its factorization.

81878526 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1438 (or 1429 counting only the distinct ones).

The product of its digits is 215040, while the sum is 45.

The square root of 81878526 is about 9048.6753726720. The cubic root of 81878526 is about 434.2335134729.

The spelling of 81878526 in words is "eighty-one million, eight hundred seventy-eight thousand, five hundred twenty-six".