201021211021220 has 24 divisors (see below), whose sum is σ = 422149852409208. Its totient is φ = 80407473120000.

The previous prime is 201021211021171. The next prime is 201021211021243. The reversal of 201021211021220 is 22120112120102.

It can be written as a sum of positive squares in 4 ways, for example, as 44875743532096 + 156145467489124 = 6698936^2 + 12495818^2 .

It is a super-2 number, since 2×201021211021220² (a number of 29 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61574531 + ... + 64756970.

It is an arithmetic number, because the mean of its divisors is an integer number (17589577183717).

Almost surely, 2^{201021211021220} is an apocalyptic number.

201021211021220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201021211021220 is an abundant number, since it is smaller than the sum of its proper divisors (221128641387988).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

201021211021220 is a wasteful number, since it uses less digits than its factorization.

201021211021220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126411071 (or 126411069 counting only the distinct ones).

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

Adding to 201021211021220 its reverse (22120112120102), we get a palindrome (223141323141322).

The spelling of 201021211021220 in words is "two hundred one trillion, twenty-one billion, two hundred eleven million, twenty-one thousand, two hundred twenty".