71311101101021 has 4 divisors (see below), whose sum is σ = 71412828778044. Its totient is φ = 71209373424000.

The previous prime is 71311101101011. The next prime is 71311101101089. The reversal of 71311101101021 is 12010110111317.

It is a happy number.

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 39674818452025 + 31636282648996 = 6298795^2 + 5624614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71311101101021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 71311101100984 and 71311101101002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71311101101011) 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, 50863837460 + ... + 50863838861.

It is an arithmetic number, because the mean of its divisors is an integer number (17853207194511).

Almost surely, 2^{71311101101021} is an apocalyptic number.

It is an amenable number.

71311101101021 is a deficient number, since it is larger than the sum of its proper divisors (101727677023).

71311101101021 is a wasteful number, since it uses less digits than its factorization.

71311101101021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101727677022.

The product of its (nonzero) digits is 42, while the sum is 20.

Adding to 71311101101021 its reverse (12010110111317), we get a palindrome (83321211212338).

The spelling of 71311101101021 in words is "seventy-one trillion, three hundred eleven billion, one hundred one million, one hundred one thousand, twenty-one".