71956985 has 4 divisors (see below), whose sum is σ = 86348388. Its totient is φ = 57565584.

The previous prime is 71956981. The next prime is 71956993. The reversal of 71956985 is 58965917.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58965917 = 971 ⋅60727.

It can be written as a sum of positive squares in 2 ways, for example, as 8404201 + 63552784 = 2899^2 + 7972^2 .

It is a cyclic number.

It is not a de Polignac number, because 71956985 - 2² = 71956981 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (71956981) 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, 7195694 + ... + 7195703.

It is an arithmetic number, because the mean of its divisors is an integer number (21587097).

Almost surely, 2^71956985 is an apocalyptic number.

It is an amenable number.

71956985 is a deficient number, since it is larger than the sum of its proper divisors (14391403).

71956985 is a wasteful number, since it uses less digits than its factorization.

71956985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14391402.

The product of its digits is 680400, while the sum is 50.

The square root of 71956985 is about 8482.7463123684. The cubic root of 71956985 is about 415.9339010642.

The spelling of 71956985 in words is "seventy-one million, nine hundred fifty-six thousand, nine hundred eighty-five".