211220222121001 has 4 divisors (see below), whose sum is σ = 211241555352004. Its totient is φ = 211198888890000.

The previous prime is 211220222120977. The next prime is 211220222121047. The reversal of 211220222121001 is 100121222022112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 138905199498025 + 72315022622976 = 11785805^2 + 8503824^2 .

It is a cyclic number.

It is not a de Polignac number, because 211220222121001 - 2²¹ = 211220220023849 is a prime.

It is a super-3 number, since 3×211220222121001³ (a number of 44 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

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 211220222121001.

It is not an unprimeable number, because it can be changed into a prime (211220222121901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10666600650 + ... + 10666620451.

It is an arithmetic number, because the mean of its divisors is an integer number (52810388838001).

Almost surely, 2^{211220222121001} is an apocalyptic number.

It is an amenable number.

211220222121001 is a deficient number, since it is larger than the sum of its proper divisors (21333231003).

211220222121001 is an equidigital number, since it uses as much as digits as its factorization.

211220222121001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21333231002.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 211220222121001 its reverse (100121222022112), we get a palindrome (311341444143113).

The spelling of 211220222121001 in words is "two hundred eleven trillion, two hundred twenty billion, two hundred twenty-two million, one hundred twenty-one thousand, one".