71691013 has 4 divisors (see below), whose sum is σ = 72496620. Its totient is φ = 70885408.

The previous prime is 71691007. The next prime is 71691017. The reversal of 71691013 is 31019617.

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

It can be written as a sum of positive squares in 2 ways, for example, as 12061729 + 59629284 = 3473^2 + 7722^2 .

It is a cyclic number.

It is not a de Polignac number, because 71691013 - 2⁵ = 71690981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71691017) 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, 402670 + ... + 402847.

It is an arithmetic number, because the mean of its divisors is an integer number (18124155).

Almost surely, 2^71691013 is an apocalyptic number.

It is an amenable number.

71691013 is a deficient number, since it is larger than the sum of its proper divisors (805607).

71691013 is an equidigital number, since it uses as much as digits as its factorization.

71691013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 805606.

The product of its (nonzero) digits is 1134, while the sum is 28.

The square root of 71691013 is about 8467.0545646051. The cubic root of 71691013 is about 415.4208012170.

The spelling of 71691013 in words is "seventy-one million, six hundred ninety-one thousand, thirteen".