71252581 has 4 divisors (see below), whose sum is σ = 71296992. Its totient is φ = 71208172.

The previous prime is 71252569. The next prime is 71252647. The reversal of 71252581 is 18525217.

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: 18525217 = 43 ⋅430819.

It is a cyclic number.

It is not a de Polignac number, because 71252581 - 2¹⁹ = 70728293 is a prime.

It is a super-2 number, since 2×71252581² = 10153860598323122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71252501) 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, 19705 + ... + 23038.

It is an arithmetic number, because the mean of its divisors is an integer number (17824248).

Almost surely, 2^71252581 is an apocalyptic number.

It is an amenable number.

71252581 is a deficient number, since it is larger than the sum of its proper divisors (44411).

71252581 is a wasteful number, since it uses less digits than its factorization.

71252581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44410.

The product of its digits is 5600, while the sum is 31.

The square root of 71252581 is about 8441.1243919279. The cubic root of 71252581 is about 414.5722228706.

Adding to 71252581 its reverse (18525217), we get a palindrome (89777798).

The spelling of 71252581 in words is "seventy-one million, two hundred fifty-two thousand, five hundred eighty-one".