20202120100021 has 24 divisors (see below), whose sum is σ = 21252417500160. Its totient is φ = 19201750752096.

The previous prime is 20202120100003. The next prime is 20202120100061. The reversal of 20202120100021 is 12000102120202.

It is a happy number.

It is not a de Polignac number, because 20202120100021 - 2⁹ = 20202120099509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20202120099974 and 20202120100010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20202120100061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 55050540 + ... + 55416298.

It is an arithmetic number, because the mean of its divisors is an integer number (885517395840).

Almost surely, 2^{20202120100021} is an apocalyptic number.

It is an amenable number.

20202120100021 is a deficient number, since it is larger than the sum of its proper divisors (1050297400139).

20202120100021 is a wasteful number, since it uses less digits than its factorization.

20202120100021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 366465 (or 366442 counting only the distinct ones).

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

Adding to 20202120100021 its reverse (12000102120202), we get a palindrome (32202222220223).

The spelling of 20202120100021 in words is "twenty trillion, two hundred two billion, one hundred twenty million, one hundred thousand, twenty-one".