71538644 has 12 divisors (see below), whose sum is σ = 125341524. Its totient is φ = 35726784.

The previous prime is 71538641. The next prime is 71538659. The reversal of 71538644 is 44683517.

It can be written as a sum of positive squares in 2 ways, for example, as 50268100 + 21270544 = 7090^2 + 4612^2 .

It is a junction number, because it is equal to n+sod(n) for n = 71538598 and 71538607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71538641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6689 + ... + 13704.

It is an arithmetic number, because the mean of its divisors is an integer number (10445127).

Almost surely, 2^71538644 is an apocalyptic number.

It is an amenable number.

71538644 is a deficient number, since it is larger than the sum of its proper divisors (53802880).

71538644 is a wasteful number, since it uses less digits than its factorization.

71538644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21274 (or 21272 counting only the distinct ones).

The product of its digits is 80640, while the sum is 38.

The square root of 71538644 is about 8458.0520215946. The cubic root of 71538644 is about 415.1262866257.

The spelling of 71538644 in words is "seventy-one million, five hundred thirty-eight thousand, six hundred forty-four".