71242513 has 4 divisors (see below), whose sum is σ = 71351280. Its totient is φ = 71133748.

The previous prime is 71242511. The next prime is 71242517. The reversal of 71242513 is 31524217.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 31524217 = 109 ⋅289213.

It is a cyclic number.

It is not a de Polignac number, because 71242513 - 2¹ = 71242511 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71242511) 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, 53395 + ... + 54712.

It is an arithmetic number, because the mean of its divisors is an integer number (17837820).

Almost surely, 2^71242513 is an apocalyptic number.

It is an amenable number.

71242513 is a deficient number, since it is larger than the sum of its proper divisors (108767).

71242513 is a wasteful number, since it uses less digits than its factorization.

71242513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108766.

The product of its digits is 1680, while the sum is 25.

The square root of 71242513 is about 8440.5280048111. The cubic root of 71242513 is about 414.5526955791.

The spelling of 71242513 in words is "seventy-one million, two hundred forty-two thousand, five hundred thirteen".