21355352171770 has 16 divisors (see below), whose sum is σ = 38669811360768. Its totient is φ = 8490990323920.

The previous prime is 21355352171749. The next prime is 21355352171807. The reversal of 21355352171770 is 7717125355312.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6393816346 + ... + 6393819685.

It is an arithmetic number, because the mean of its divisors is an integer number (2416863210048).

Almost surely, 2^{21355352171770} is an apocalyptic number.

21355352171770 is a deficient number, since it is larger than the sum of its proper divisors (17314459188998).

21355352171770 is a wasteful number, since it uses less digits than its factorization.

21355352171770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12787636205.

The product of its (nonzero) digits is 1543500, while the sum is 49.

The spelling of 21355352171770 in words is "twenty-one trillion, three hundred fifty-five billion, three hundred fifty-two million, one hundred seventy-one thousand, seven hundred seventy".