71185220641 has 4 divisors (see below), whose sum is σ = 71876339392. Its totient is φ = 70494101892.

The previous prime is 71185220629. The next prime is 71185220647. The reversal of 71185220641 is 14602258117.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71185220641 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 71185220641.

It is not an unprimeable number, because it can be changed into a prime (71185220647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 345559221 + ... + 345559426.

It is an arithmetic number, because the mean of its divisors is an integer number (17969084848).

Almost surely, 2^71185220641 is an apocalyptic number.

It is an amenable number.

71185220641 is a deficient number, since it is larger than the sum of its proper divisors (691118751).

71185220641 is a wasteful number, since it uses less digits than its factorization.

71185220641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 691118750.

The product of its (nonzero) digits is 26880, while the sum is 37.

Adding to 71185220641 its reverse (14602258117), we get a palindrome (85787478758).

The spelling of 71185220641 in words is "seventy-one billion, one hundred eighty-five million, two hundred twenty thousand, six hundred forty-one".