81629337599 has 4 divisors (see below), whose sum is σ = 83366132064. Its totient is φ = 79892543136.

The previous prime is 81629337583. The next prime is 81629337607. The reversal of 81629337599 is 99573392618.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81629337599 - 2⁴ = 81629337583 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81629331599) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 868397162 + ... + 868397255.

It is an arithmetic number, because the mean of its divisors is an integer number (20841533016).

Almost surely, 2^81629337599 is an apocalyptic number.

81629337599 is a deficient number, since it is larger than the sum of its proper divisors (1736794465).

81629337599 is a wasteful number, since it uses less digits than its factorization.

81629337599 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1736794464.

The product of its digits is 22044960, while the sum is 62.

The spelling of 81629337599 in words is "eighty-one billion, six hundred twenty-nine million, three hundred thirty-seven thousand, five hundred ninety-nine".