71982517 has 4 divisors (see below), whose sum is σ = 72250380. Its totient is φ = 71714656.

The previous prime is 71982499. The next prime is 71982551. The reversal of 71982517 is 71528917.

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

It can be written as a sum of positive squares in 2 ways, for example, as 6922161 + 65060356 = 2631^2 + 8066^2 .

It is a cyclic number.

It is not a de Polignac number, because 71982517 - 2¹⁹ = 71458229 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 71982517.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71982557) 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, 133528 + ... + 134065.

It is an arithmetic number, because the mean of its divisors is an integer number (18062595).

Almost surely, 2^71982517 is an apocalyptic number.

It is an amenable number.

71982517 is a deficient number, since it is larger than the sum of its proper divisors (267863).

71982517 is a wasteful number, since it uses less digits than its factorization.

71982517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267862.

The product of its digits is 35280, while the sum is 40.

The square root of 71982517 is about 8484.2511160385. The cubic root of 71982517 is about 415.9830895647.

The spelling of 71982517 in words is "seventy-one million, nine hundred eighty-two thousand, five hundred seventeen".