71193721 has 4 divisors (see below), whose sum is σ = 71531344. Its totient is φ = 70856100.

The previous prime is 71193713. The next prime is 71193737. The reversal of 71193721 is 12739117.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 71193721 - 2³ = 71193713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71193751) 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, 168495 + ... + 168916.

It is an arithmetic number, because the mean of its divisors is an integer number (17882836).

Almost surely, 2^71193721 is an apocalyptic number.

It is an amenable number.

71193721 is a deficient number, since it is larger than the sum of its proper divisors (337623).

71193721 is a wasteful number, since it uses less digits than its factorization.

71193721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 337622.

The product of its digits is 2646, while the sum is 31.

The square root of 71193721 is about 8437.6371692554. The cubic root of 71193721 is about 414.4580354592.

The spelling of 71193721 in words is "seventy-one million, one hundred ninety-three thousand, seven hundred twenty-one".