201021202021 has 8 divisors (see below), whose sum is σ = 202130641944. Its totient is φ = 199912661760.

The previous prime is 201021202007. The next prime is 201021202051. The reversal of 201021202021 is 120202120102.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 32802280996 + 168218921025 = 181114^2 + 410145^2 .

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 201021202021 - 2⁵ = 201021201989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201021201992 and 201021202010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201021202051) 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, 225681 + ... + 673033.

It is an arithmetic number, because the mean of its divisors is an integer number (25266330243).

Almost surely, 2^201021202021 is an apocalyptic number.

It is an amenable number.

201021202021 is a deficient number, since it is larger than the sum of its proper divisors (1109439923).

201021202021 is a wasteful number, since it uses less digits than its factorization.

201021202021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 449831.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 201021202021 its reverse (120202120102), we get a palindrome (321223322123).

The spelling of 201021202021 in words is "two hundred one billion, twenty-one million, two hundred two thousand, twenty-one".