10012121221 has 4 divisors (see below), whose sum is σ = 10012456000. Its totient is φ = 10011786444.

The previous prime is 10012121159. The next prime is 10012121267. The reversal of 10012121221 is 12212121001.

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 a cyclic number.

It is not a de Polignac number, because 10012121221 - 2²¹ = 10010024069 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 (10010121221) 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, 117591 + ... + 183988.

It is an arithmetic number, because the mean of its divisors is an integer number (2503114000).

Almost surely, 2^10012121221 is an apocalyptic number.

It is an amenable number.

10012121221 is a deficient number, since it is larger than the sum of its proper divisors (334779).

10012121221 is an equidigital number, since it uses as much as digits as its factorization.

10012121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334778.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 10012121221 its reverse (12212121001), we get a palindrome (22224242222).

The spelling of 10012121221 in words is "ten billion, twelve million, one hundred twenty-one thousand, two hundred twenty-one".