71564731 has 4 divisors (see below), whose sum is σ = 81788272. Its totient is φ = 61341192.

The previous prime is 71564687. The next prime is 71564741. The reversal of 71564731 is 13746517.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13746517 = 251 ⋅54767.

It is a cyclic number.

It is not a de Polignac number, because 71564731 - 2⁹ = 71564219 is a prime.

It is a super-2 number, since 2×71564731² = 10243021446204722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71564741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5111760 + ... + 5111773.

It is an arithmetic number, because the mean of its divisors is an integer number (20447068).

Almost surely, 2^71564731 is an apocalyptic number.

71564731 is a deficient number, since it is larger than the sum of its proper divisors (10223541).

71564731 is a wasteful number, since it uses less digits than its factorization.

71564731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10223540.

The product of its digits is 17640, while the sum is 34.

The square root of 71564731 is about 8459.5940209918. The cubic root of 71564731 is about 415.1767399321.

The spelling of 71564731 in words is "seventy-one million, five hundred sixty-four thousand, seven hundred thirty-one".