71247749 has 4 divisors (see below), whose sum is σ = 71272320. Its totient is φ = 71223180.

The previous prime is 71247727. The next prime is 71247779. The reversal of 71247749 is 94774217.

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 a de Polignac number, because none of the positive numbers 2^k-71247749 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 (71247779) 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, 7247 + ... + 13964.

It is an arithmetic number, because the mean of its divisors is an integer number (17818080).

Almost surely, 2^71247749 is an apocalyptic number.

It is an amenable number.

71247749 is a deficient number, since it is larger than the sum of its proper divisors (24571).

71247749 is a wasteful number, since it uses less digits than its factorization.

71247749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24570.

The product of its digits is 98784, while the sum is 41.

The square root of 71247749 is about 8440.8381692815. The cubic root of 71247749 is about 414.5628512416.

The spelling of 71247749 in words is "seventy-one million, two hundred forty-seven thousand, seven hundred forty-nine".