81629622 has 72 divisors (see below), whose sum is σ = 192173904. Its totient is φ = 24976512.

The previous prime is 81629621. The next prime is 81629629. The reversal of 81629622 is 22692618.

It is a happy number.

81629622 is a `hidden beast` number, since 8 + 1 + 6 + 29 + 622 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81629621) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1118178 + ... + 1118250.

It is an arithmetic number, because the mean of its divisors is an integer number (2669082).

Almost surely, 2^81629622 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81629622, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96086952).

81629622 is an abundant number, since it is smaller than the sum of its proper divisors (110544282).

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

81629622 is a wasteful number, since it uses less digits than its factorization.

81629622 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214 (or 138 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 81629622 is about 9034.9112889945. The cubic root of 81629622 is about 433.7930554364.

The spelling of 81629622 in words is "eighty-one million, six hundred twenty-nine thousand, six hundred twenty-two".