201210121021 has 32 divisors (see below), whose sum is σ = 249087541248. Its totient is φ = 158271744960.

The previous prime is 201210121019. The next prime is 201210121027. The reversal of 201210121021 is 120121012102.

It is not a de Polignac number, because 201210121021 - 2¹ = 201210121019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a junction number, because it is equal to n+sod(n) for n = 201210120992 and 201210121010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201210121027) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 51497950 + ... + 51501856.

It is an arithmetic number, because the mean of its divisors is an integer number (7783985664).

Almost surely, 2^201210121021 is an apocalyptic number.

It is an amenable number.

201210121021 is a deficient number, since it is larger than the sum of its proper divisors (47877420227).

201210121021 is a wasteful number, since it uses less digits than its factorization.

201210121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7081.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 201210121021 its reverse (120121012102), we get a palindrome (321331133123).

The spelling of 201210121021 in words is "two hundred one billion, two hundred ten million, one hundred twenty-one thousand, twenty-one".