20102021221 has 4 divisors (see below), whose sum is σ = 20102975200. Its totient is φ = 20101067244.

The previous prime is 20102021179. The next prime is 20102021279. The reversal of 20102021221 is 12212020102.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12212020102 = 2 ⋅6106010051.

It is a cyclic number.

It is not a de Polignac number, because 20102021221 - 2³³ = 11512086629 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 (20102021921) 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, 444651 + ... + 487768.

It is an arithmetic number, because the mean of its divisors is an integer number (5025743800).

Almost surely, 2^20102021221 is an apocalyptic number.

It is an amenable number.

20102021221 is a deficient number, since it is larger than the sum of its proper divisors (953979).

20102021221 is an equidigital number, since it uses as much as digits as its factorization.

20102021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 953978.

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

Adding to 20102021221 its reverse (12212020102), we get a palindrome (32314041323).

The spelling of 20102021221 in words is "twenty billion, one hundred two million, twenty-one thousand, two hundred twenty-one".