21012121102201 has 8 divisors (see below), whose sum is σ = 21049553133000. Its totient is φ = 20974719870720.

The previous prime is 21012121102183. The next prime is 21012121102213. The reversal of 21012121102201 is 10220112121012.

It can be written as a sum of positive squares in 4 ways, for example, as 600158540601 + 20411962561600 = 774699^2 + 4517960^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21012121102201 - 2²³ = 21012112713593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21012121102241) 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, 6333946 + ... + 9063283.

It is an arithmetic number, because the mean of its divisors is an integer number (2631194141625).

Almost surely, 2^{21012121102201} is an apocalyptic number.

It is an amenable number.

21012121102201 is a deficient number, since it is larger than the sum of its proper divisors (37432030799).

21012121102201 is a wasteful number, since it uses less digits than its factorization.

21012121102201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15399659.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21012121102201 its reverse (10220112121012), we get a palindrome (31232233223213).

The spelling of 21012121102201 in words is "twenty-one trillion, twelve billion, one hundred twenty-one million, one hundred two thousand, two hundred one".