201021201022121 has 8 divisors (see below), whose sum is σ = 212869181247624. Its totient is φ = 189175798984960.

The previous prime is 201021201022067. The next prime is 201021201022153. The reversal of 201021201022121 is 121220102120102.

It can be written as a sum of positive squares in 4 ways, for example, as 3893676097600 + 197127524924521 = 1973240^2 + 14040211^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201021201022121 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 201021201022121.

It is not an unprimeable number, because it can be changed into a prime (201021201022171) 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, 644386550 + ... + 644698431.

It is an arithmetic number, because the mean of its divisors is an integer number (26608647655953).

Almost surely, 2^{201021201022121} is an apocalyptic number.

It is an amenable number.

201021201022121 is a deficient number, since it is larger than the sum of its proper divisors (11847980225503).

201021201022121 is a wasteful number, since it uses less digits than its factorization.

201021201022121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1289094171.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 201021201022121 its reverse (121220102120102), we get a palindrome (322241303142223).

The spelling of 201021201022121 in words is "two hundred one trillion, twenty-one billion, two hundred one million, twenty-two thousand, one hundred twenty-one".