71531397 has 64 divisors (see below), whose sum is σ = 127388160. Its totient is φ = 38817792.

The previous prime is 71531387. The next prime is 71531401. The reversal of 71531397 is 79313517.

It is not a de Polignac number, because 71531397 - 2⁷ = 71531269 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71531377) 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 63 ways as a sum of consecutive naturals, for example, 370533 + ... + 370725.

It is an arithmetic number, because the mean of its divisors is an integer number (1990440).

Almost surely, 2^71531397 is an apocalyptic number.

It is an amenable number.

71531397 is a deficient number, since it is larger than the sum of its proper divisors (55856763).

71531397 is a wasteful number, since it uses less digits than its factorization.

71531397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 299 (or 293 counting only the distinct ones).

The product of its digits is 19845, while the sum is 36.

The square root of 71531397 is about 8457.6236024075. The cubic root of 71531397 is about 415.1122684596.

The spelling of 71531397 in words is "seventy-one million, five hundred thirty-one thousand, three hundred ninety-seven".