71649809525 has 24 divisors (see below), whose sum is σ = 101553202560. Its totient is φ = 49123949760.

The previous prime is 71649809513. The next prime is 71649809531. The reversal of 71649809525 is 52590894617.

It is not a de Polignac number, because 71649809525 - 2¹⁰ = 71649808501 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1310027 + ... + 1363623.

It is an arithmetic number, because the mean of its divisors is an integer number (4231383440).

Almost surely, 2^71649809525 is an apocalyptic number.

It is an amenable number.

71649809525 is a deficient number, since it is larger than the sum of its proper divisors (29903393035).

71649809525 is a wasteful number, since it uses less digits than its factorization.

71649809525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61253 (or 61248 counting only the distinct ones).

The product of its (nonzero) digits is 5443200, while the sum is 56.

The spelling of 71649809525 in words is "seventy-one billion, six hundred forty-nine million, eight hundred nine thousand, five hundred twenty-five".