81909035715 has 16 divisors (see below), whose sum is σ = 141135569568. Its totient is φ = 40324448256.

The previous prime is 81909035653. The next prime is 81909035737. The reversal of 81909035715 is 51753090918.

It is not a de Polignac number, because 81909035715 - 2⁹ = 81909035203 is a prime.

It is a super-2 number, since 2×81909035715² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 210022974 + ... + 210023363.

It is an arithmetic number, because the mean of its divisors is an integer number (8820973098).

Almost surely, 2^81909035715 is an apocalyptic number.

81909035715 is a deficient number, since it is larger than the sum of its proper divisors (59226533853).

81909035715 is a wasteful number, since it uses less digits than its factorization.

81909035715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 420046358.

The product of its (nonzero) digits is 340200, while the sum is 48.

The spelling of 81909035715 in words is "eighty-one billion, nine hundred nine million, thirty-five thousand, seven hundred fifteen".