71957131 has 2 divisors, whose sum is σ = 71957132. Its totient is φ = 71957130.

The previous prime is 71957111. The next prime is 71957143. The reversal of 71957131 is 13175917.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71957131 is a prime.

It is a super-2 number, since 2×71957131² = 10355657403502322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (71957111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35978565 + 35978566.

It is an arithmetic number, because the mean of its divisors is an integer number (35978566).

Almost surely, 2^71957131 is an apocalyptic number.

71957131 is a deficient number, since it is larger than the sum of its proper divisors (1).

71957131 is an equidigital number, since it uses as much as digits as its factorization.

71957131 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6615, while the sum is 34.

The square root of 71957131 is about 8482.7549180676. The cubic root of 71957131 is about 415.9341823726.

The spelling of 71957131 in words is "seventy-one million, nine hundred fifty-seven thousand, one hundred thirty-one".