81751626 has 64 divisors (see below), whose sum is σ = 199382400. Its totient is φ = 24624000.

The previous prime is 81751613. The next prime is 81751687. The reversal of 81751626 is 62615718.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 135726 + ... + 136326.

It is an arithmetic number, because the mean of its divisors is an integer number (3115350).

Almost surely, 2^81751626 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81751626, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99691200).

81751626 is an abundant number, since it is smaller than the sum of its proper divisors (117630774).

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

81751626 is a wasteful number, since it uses less digits than its factorization.

81751626 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 852 (or 846 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 81751626 is about 9041.6605775709. The cubic root of 81751626 is about 434.0090642065.

It can be divided in two parts, 8175 and 1626, that added together give a square (9801 = 99²).

The spelling of 81751626 in words is "eighty-one million, seven hundred fifty-one thousand, six hundred twenty-six".