71721493 has 8 divisors (see below), whose sum is σ = 72938880. Its totient is φ = 70512000.

The previous prime is 71721491. The next prime is 71721499. The reversal of 71721493 is 39412717.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 71721493 - 2¹ = 71721491 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71721491) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18021 + ... + 21637.

It is an arithmetic number, because the mean of its divisors is an integer number (9117360).

Almost surely, 2^71721493 is an apocalyptic number.

It is an amenable number.

71721493 is a deficient number, since it is larger than the sum of its proper divisors (1217387).

71721493 is a wasteful number, since it uses less digits than its factorization.

71721493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3947.

The product of its digits is 10584, while the sum is 34.

The square root of 71721493 is about 8468.8542908708. The cubic root of 71721493 is about 415.4796660196.

The spelling of 71721493 in words is "seventy-one million, seven hundred twenty-one thousand, four hundred ninety-three".