2171256521711 has 8 divisors (see below), whose sum is σ = 2172052112880. Its totient is φ = 2170461054528.

The previous prime is 2171256521653. The next prime is 2171256521717. The reversal of 2171256521711 is 1171256521712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2171256521711 - 2⁶ = 2171256521647 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 (2171256521717) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47606060 + ... + 47651646.

It is an arithmetic number, because the mean of its divisors is an integer number (271506514110).

Almost surely, 2^{2171256521711} is an apocalyptic number.

2171256521711 is a deficient number, since it is larger than the sum of its proper divisors (795591169).

2171256521711 is a wasteful number, since it uses less digits than its factorization.

2171256521711 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61993.

The product of its digits is 58800, while the sum is 41.

Subtracting from 2171256521711 its reverse (1171256521712), we obtain a palindrome (999999999999).

The spelling of 2171256521711 in words is "two trillion, one hundred seventy-one billion, two hundred fifty-six million, five hundred twenty-one thousand, seven hundred eleven".