71720503735 has 4 divisors (see below), whose sum is σ = 86064604488. Its totient is φ = 57376402984.

The previous prime is 71720503727. The next prime is 71720503753. The reversal of 71720503735 is 53730502717.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 53730502717 = 107 ⋅502154231.

It is a cyclic number.

It is not a de Polignac number, because 71720503735 - 2³ = 71720503727 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7172050369 + ... + 7172050378.

It is an arithmetic number, because the mean of its divisors is an integer number (21516151122).

Almost surely, 2^71720503735 is an apocalyptic number.

71720503735 is a deficient number, since it is larger than the sum of its proper divisors (14344100753).

71720503735 is a wasteful number, since it uses less digits than its factorization.

71720503735 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14344100752.

The product of its (nonzero) digits is 154350, while the sum is 40.

The spelling of 71720503735 in words is "seventy-one billion, seven hundred twenty million, five hundred three thousand, seven hundred thirty-five".