81031729603 has 4 divisors (see below), whose sum is σ = 88398250488. Its totient is φ = 73665208720.

The previous prime is 81031729577. The next prime is 81031729607. The reversal of 81031729603 is 30692713018.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81031729603 is a prime.

It is a super-2 number, since 2×81031729603² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81031729607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3683260426 + ... + 3683260447.

It is an arithmetic number, because the mean of its divisors is an integer number (22099562622).

Almost surely, 2^81031729603 is an apocalyptic number.

81031729603 is a deficient number, since it is larger than the sum of its proper divisors (7366520885).

81031729603 is a wasteful number, since it uses less digits than its factorization.

81031729603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7366520884.

The product of its (nonzero) digits is 54432, while the sum is 40.

The spelling of 81031729603 in words is "eighty-one billion, thirty-one million, seven hundred twenty-nine thousand, six hundred three".