71313131 has 4 divisors (see below), whose sum is σ = 71590872. Its totient is φ = 71035392.

The previous prime is 71313127. The next prime is 71313163. The reversal of 71313131 is 13131317.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 71313131 - 2² = 71313127 is a prime.

It is a super-2 number, since 2×71313131² = 10171125306046322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71313191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 138485 + ... + 138998.

It is an arithmetic number, because the mean of its divisors is an integer number (17897718).

Almost surely, 2^71313131 is an apocalyptic number.

71313131 is a deficient number, since it is larger than the sum of its proper divisors (277741).

71313131 is a wasteful number, since it uses less digits than its factorization.

71313131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 277740.

The product of its digits is 189, while the sum is 20.

The square root of 71313131 is about 8444.7102377761. The cubic root of 71313131 is about 414.6896232533.

Adding to 71313131 its reverse (13131317), we get a palindrome (84444448).

It can be divided in two parts, 71313 and 131, that multiplied together give a triangular number (9342003 = T₄₃₂₂).

The spelling of 71313131 in words is "seventy-one million, three hundred thirteen thousand, one hundred thirty-one".