71843813 has 4 divisors (see below), whose sum is σ = 71874528. Its totient is φ = 71813100.

The previous prime is 71843797. The next prime is 71843831. The reversal of 71843813 is 31834817.

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: 31834817 = 7 ⋅4547831.

It is a cyclic number.

It is not a de Polignac number, because 71843813 - 2⁴ = 71843797 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71843843) 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, 11531 + ... + 16632.

It is an arithmetic number, because the mean of its divisors is an integer number (17968632).

Almost surely, 2^71843813 is an apocalyptic number.

It is an amenable number.

71843813 is a deficient number, since it is larger than the sum of its proper divisors (30715).

71843813 is a wasteful number, since it uses less digits than its factorization.

71843813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30714.

The product of its digits is 16128, while the sum is 35.

The square root of 71843813 is about 8476.0729704268. The cubic root of 71843813 is about 415.7157301160.

The spelling of 71843813 in words is "seventy-one million, eight hundred forty-three thousand, eight hundred thirteen".