71631641 has 4 divisors (see below), whose sum is σ = 71706384. Its totient is φ = 71556900.

The previous prime is 71631631. The next prime is 71631647. The reversal of 71631641 is 14613617.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 14613617 = 31 ⋅471407.

It is a cyclic number.

It is not a de Polignac number, because 71631641 - 2¹⁰ = 71630617 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (71631647) 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, 35915 + ... + 37856.

It is an arithmetic number, because the mean of its divisors is an integer number (17926596).

Almost surely, 2^71631641 is an apocalyptic number.

It is an amenable number.

71631641 is a deficient number, since it is larger than the sum of its proper divisors (74743).

71631641 is an equidigital number, since it uses as much as digits as its factorization.

71631641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74742.

The product of its digits is 3024, while the sum is 29.

The square root of 71631641 is about 8463.5477785619. The cubic root of 71631641 is about 415.3060905318.

The spelling of 71631641 in words is "seventy-one million, six hundred thirty-one thousand, six hundred forty-one".