81220342829 has 8 divisors (see below), whose sum is σ = 83844284160. Its totient is φ = 78596647200.

The previous prime is 81220342799. The next prime is 81220342831. The reversal of 81220342829 is 92824302218.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81220342829 - 2¹² = 81220338733 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 (81220342849) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 804242 + ... + 899580.

It is an arithmetic number, because the mean of its divisors is an integer number (10480535520).

Almost surely, 2^81220342829 is an apocalyptic number.

It is an amenable number.

81220342829 is a deficient number, since it is larger than the sum of its proper divisors (2623941331).

81220342829 is a wasteful number, since it uses less digits than its factorization.

81220342829 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122851.

The product of its (nonzero) digits is 110592, while the sum is 41.

The spelling of 81220342829 in words is "eighty-one billion, two hundred twenty million, three hundred forty-two thousand, eight hundred twenty-nine".