81629696 has 80 divisors (see below), whose sum is σ = 174155520. Its totient is φ = 38154240.

The previous prime is 81629689. The next prime is 81629707. The reversal of 81629696 is 69692618.

It is a self number, because there is not a number n which added to its sum of digits gives 81629696.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 587195 + ... + 587333.

It is an arithmetic number, because the mean of its divisors is an integer number (2176944).

Almost surely, 2^81629696 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81629696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87077760).

81629696 is an abundant number, since it is smaller than the sum of its proper divisors (92525824).

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

81629696 is a wasteful number, since it uses less digits than its factorization.

81629696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225 (or 209 counting only the distinct ones).

The product of its digits is 279936, while the sum is 47.

The square root of 81629696 is about 9034.9153842192. The cubic root of 81629696 is about 433.7931865190.

The spelling of 81629696 in words is "eighty-one million, six hundred twenty-nine thousand, six hundred ninety-six".