71861643 has 48 divisors (see below), whose sum is σ = 124540416. Its totient is φ = 39070080.

The previous prime is 71861611. The next prime is 71861651. The reversal of 71861643 is 34616817.

71861643 is a `hidden beast` number, since 7 + 1 + 8 + 6 + 1 + 643 = 666.

It is not a de Polignac number, because 71861643 - 2⁵ = 71861611 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 71861598 and 71861607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71861653) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 110746 + ... + 111392.

It is an arithmetic number, because the mean of its divisors is an integer number (2594592).

Almost surely, 2^71861643 is an apocalyptic number.

71861643 is a deficient number, since it is larger than the sum of its proper divisors (52678773).

71861643 is a wasteful number, since it uses less digits than its factorization.

71861643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 744 (or 741 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 71861643 is about 8477.1246894215. The cubic root of 71861643 is about 415.7501176671.

The spelling of 71861643 in words is "seventy-one million, eight hundred sixty-one thousand, six hundred forty-three".