71720497426 has 4 divisors (see below), whose sum is σ = 107580746142. Its totient is φ = 35860248712.

The previous prime is 71720497397. The next prime is 71720497489. The reversal of 71720497426 is 62479402717.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 62479402717 = 73 ⋅855882229.

It can be written as a sum of positive squares in only one way, i.e., 69011815401 + 2708682025 = 262701^2 + 52045^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 71720497426.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 17930124355 + ... + 17930124358.

Almost surely, 2^71720497426 is an apocalyptic number.

71720497426 is a deficient number, since it is larger than the sum of its proper divisors (35860248716).

71720497426 is a wasteful number, since it uses less digits than its factorization.

71720497426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35860248715.

The product of its (nonzero) digits is 1185408, while the sum is 49.

The spelling of 71720497426 in words is "seventy-one billion, seven hundred twenty million, four hundred ninety-seven thousand, four hundred twenty-six".