81285229079 has 16 divisors (see below), whose sum is σ = 83051291520. Its totient is φ = 79533888000.

The previous prime is 81285229061. The next prime is 81285229087. The reversal of 81285229079 is 97092258218.

It is a cyclic number.

It is not a de Polignac number, because 81285229079 - 2⁸ = 81285228823 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81285229079.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81285229019) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17215439 + ... + 17220159.

It is an arithmetic number, because the mean of its divisors is an integer number (5190705720).

Almost surely, 2^81285229079 is an apocalyptic number.

81285229079 is a deficient number, since it is larger than the sum of its proper divisors (1766062441).

81285229079 is a wasteful number, since it uses less digits than its factorization.

81285229079 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6202.

The product of its (nonzero) digits is 1451520, while the sum is 53.

The spelling of 81285229079 in words is "eighty-one billion, two hundred eighty-five million, two hundred twenty-nine thousand, seventy-nine".