71564231 has 4 divisors (see below), whose sum is σ = 71581272. Its totient is φ = 71547192.

The previous prime is 71564219. The next prime is 71564243. The reversal of 71564231 is 13246517.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 13246517 = 31 ⋅427307.

It is an interprime number because it is at equal distance from previous prime (71564219) and next prime (71564243).

It is a cyclic number.

It is not a de Polignac number, because 71564231 - 2⁶ = 71564167 is a prime.

It is a super-2 number, since 2×71564231² = 10242878317242722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 71564194 and 71564203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71564261) 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, 2741 + ... + 12273.

It is an arithmetic number, because the mean of its divisors is an integer number (17895318).

Almost surely, 2^71564231 is an apocalyptic number.

71564231 is a deficient number, since it is larger than the sum of its proper divisors (17041).

71564231 is an equidigital number, since it uses as much as digits as its factorization.

71564231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17040.

The product of its digits is 5040, while the sum is 29.

The square root of 71564231 is about 8459.5644686946. The cubic root of 71564231 is about 415.1757730272.

It can be divided in two parts, 715 and 64231, that added together give a palindrome (64946).

The spelling of 71564231 in words is "seventy-one million, five hundred sixty-four thousand, two hundred thirty-one".