71671931 has 4 divisors (see below), whose sum is σ = 71688864. Its totient is φ = 71655000.

The previous prime is 71671921. The next prime is 71671981. The reversal of 71671931 is 13917617.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 71671931 - 2¹⁸ = 71409787 is a prime.

It is a super-2 number, since 2×71671931² = 10273731386537522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 71671891 and 71671900.

It is not an unprimeable number, because it can be changed into a prime (71671921) 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, 4181 + ... + 12681.

It is an arithmetic number, because the mean of its divisors is an integer number (17922216).

Almost surely, 2^71671931 is an apocalyptic number.

71671931 is a deficient number, since it is larger than the sum of its proper divisors (16933).

71671931 is an equidigital number, since it uses as much as digits as its factorization.

71671931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16932.

The product of its digits is 7938, while the sum is 35.

The square root of 71671931 is about 8465.9276514745. The cubic root of 71671931 is about 415.3839404222.

The spelling of 71671931 in words is "seventy-one million, six hundred seventy-one thousand, nine hundred thirty-one".