21555773046671 has 16 divisors (see below), whose sum is σ = 22174115521536. Its totient is φ = 20942777995776.

The previous prime is 21555773046653. The next prime is 21555773046673. The reversal of 21555773046671 is 17664037755512.

It is a cyclic number.

It is not a de Polignac number, because 21555773046671 - 2¹⁴ = 21555773030287 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21555773046671.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21555773046673) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68251106 + ... + 68566208.

It is an arithmetic number, because the mean of its divisors is an integer number (1385882220096).

Almost surely, 2^{21555773046671} is an apocalyptic number.

21555773046671 is a deficient number, since it is larger than the sum of its proper divisors (618342474865).

21555773046671 is a wasteful number, since it uses less digits than its factorization.

21555773046671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323582.

The product of its (nonzero) digits is 37044000, while the sum is 59.

The spelling of 21555773046671 in words is "twenty-one trillion, five hundred fifty-five billion, seven hundred seventy-three million, forty-six thousand, six hundred seventy-one".