81626706 has 96 divisors (see below), whose sum is σ = 212284800. Its totient is φ = 22176000.

The previous prime is 81626693. The next prime is 81626711. The reversal of 81626706 is 60762618.

It is a happy number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 325081 + ... + 325331.

It is an arithmetic number, because the mean of its divisors is an integer number (2211300).

Almost surely, 2^81626706 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81626706, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106142400).

81626706 is an abundant number, since it is smaller than the sum of its proper divisors (130658094).

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

81626706 is a wasteful number, since it uses less digits than its factorization.

81626706 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384 (or 381 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 81626706 is about 9034.7499135283. The cubic root of 81626706 is about 433.7878900092.

The spelling of 81626706 in words is "eighty-one million, six hundred twenty-six thousand, seven hundred six".