81909035707 has 16 divisors (see below), whose sum is σ = 88046907552. Its totient is φ = 75918458880.

The previous prime is 81909035653. The next prime is 81909035737. The reversal of 81909035707 is 70753090918.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81909035707 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81909035737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5050203 + ... + 5066395.

It is an arithmetic number, because the mean of its divisors is an integer number (5502931722).

Almost surely, 2^81909035707 is an apocalyptic number.

81909035707 is a deficient number, since it is larger than the sum of its proper divisors (6137871845).

81909035707 is a wasteful number, since it uses less digits than its factorization.

81909035707 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20718.

The product of its (nonzero) digits is 476280, while the sum is 49.

The spelling of 81909035707 in words is "eighty-one billion, nine hundred nine million, thirty-five thousand, seven hundred seven".