20211220101 has 4 divisors (see below), whose sum is σ = 26948293472. Its totient is φ = 13474146732.

The previous prime is 20211220063. The next prime is 20211220147. The reversal of 20211220101 is 10102211202.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 20211220101 - 2¹⁸ = 20210957957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211220171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3368536681 + ... + 3368536686.

It is an arithmetic number, because the mean of its divisors is an integer number (6737073368).

Almost surely, 2^20211220101 is an apocalyptic number.

It is an amenable number.

20211220101 is a deficient number, since it is larger than the sum of its proper divisors (6737073371).

20211220101 is an equidigital number, since it uses as much as digits as its factorization.

20211220101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6737073370.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 20211220101 its reverse (10102211202), we get a palindrome (30313431303).

The spelling of 20211220101 in words is "twenty billion, two hundred eleven million, two hundred twenty thousand, one hundred one".