81635429805 has 8 divisors (see below), whose sum is σ = 130616687712. Its totient is φ = 43538895888.

The previous prime is 81635429801. The next prime is 81635429893. The reversal of 81635429805 is 50892453618.

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

It is not a de Polignac number, because 81635429805 - 2² = 81635429801 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81635429801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2721180979 + ... + 2721181008.

It is an arithmetic number, because the mean of its divisors is an integer number (16327085964).

Almost surely, 2^81635429805 is an apocalyptic number.

It is an amenable number.

81635429805 is a deficient number, since it is larger than the sum of its proper divisors (48981257907).

81635429805 is a wasteful number, since it uses less digits than its factorization.

81635429805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5442361995.

The product of its (nonzero) digits is 2073600, while the sum is 51.

The spelling of 81635429805 in words is "eighty-one billion, six hundred thirty-five million, four hundred twenty-nine thousand, eight hundred five".