71256987 has 6 divisors (see below), whose sum is σ = 102926772. Its totient is φ = 47504652.

The previous prime is 71256961. The next prime is 71256989. The reversal of 71256987 is 78965217.

71256987 is a `hidden beast` number, since 7 + 1 + 2 + 569 + 87 = 666.

It is not a de Polignac number, because 71256987 - 2⁶ = 71256923 is a prime.

It is not an unprimeable number, because it can be changed into a prime (71256989) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3958713 + ... + 3958730.

It is an arithmetic number, because the mean of its divisors is an integer number (17154462).

Almost surely, 2^71256987 is an apocalyptic number.

71256987 is a deficient number, since it is larger than the sum of its proper divisors (31669785).

71256987 is a wasteful number, since it uses less digits than its factorization.

71256987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7917449 (or 7917446 counting only the distinct ones).

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

The square root of 71256987 is about 8441.3853720820. The cubic root of 71256987 is about 414.5807679064.

The spelling of 71256987 in words is "seventy-one million, two hundred fifty-six thousand, nine hundred eighty-seven".