20210666121 has 24 divisors (see below), whose sum is σ = 31115170944. Its totient is φ = 12597206400.

The previous prime is 20210666059. The next prime is 20210666123. The reversal of 20210666121 is 12166601202.

It is not a de Polignac number, because 20210666121 - 2¹⁴ = 20210649737 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20210666123) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 414301 + ... + 460506.

It is an arithmetic number, because the mean of its divisors is an integer number (1296465456).

Almost surely, 2^20210666121 is an apocalyptic number.

It is an amenable number.

20210666121 is a deficient number, since it is larger than the sum of its proper divisors (10904504823).

20210666121 is a wasteful number, since it uses less digits than its factorization.

20210666121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 874981 (or 874978 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The spelling of 20210666121 in words is "twenty billion, two hundred ten million, six hundred sixty-six thousand, one hundred twenty-one".