71657028009 has 48 divisors (see below), whose sum is σ = 119313006592. Its totient is φ = 40593589344.

The previous prime is 71657027989. The next prime is 71657028071. The reversal of 71657028009 is 90082075617.

71657028009 is a `hidden beast` number, since 71 + 6 + 570 + 2 + 8 + 0 + 0 + 9 = 666.

It is not a de Polignac number, because 71657028009 - 2¹⁶ = 71656962473 is a prime.

It is a super-2 number, since 2×71657028009² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71657008009) 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, 14263272 + ... + 14268294.

Almost surely, 2^71657028009 is an apocalyptic number.

It is an amenable number.

71657028009 is a deficient number, since it is larger than the sum of its proper divisors (47655978583).

71657028009 is a wasteful number, since it uses less digits than its factorization.

71657028009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6946 (or 6943 counting only the distinct ones).

The product of its (nonzero) digits is 211680, while the sum is 45.

The spelling of 71657028009 in words is "seventy-one billion, six hundred fifty-seven million, twenty-eight thousand, nine".