2101242221 has 4 divisors (see below), whose sum is σ = 2262876252. Its totient is φ = 1939608192.

The previous prime is 2101242181. The next prime is 2101242271. The reversal of 2101242221 is 1222421012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 857904100 + 1243338121 = 29290^2 + 35261^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2101242221 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2101242221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2101242271) 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, 80816996 + ... + 80817021.

It is an arithmetic number, because the mean of its divisors is an integer number (565719063).

Almost surely, 2^2101242221 is an apocalyptic number.

It is an amenable number.

2101242221 is a deficient number, since it is larger than the sum of its proper divisors (161634031).

2101242221 is a wasteful number, since it uses less digits than its factorization.

2101242221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161634030.

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 2101242221 is about 45839.3086880681. The cubic root of 2101242221 is about 1280.8316171733.

Adding to 2101242221 its reverse (1222421012), we get a palindrome (3323663233).

The spelling of 2101242221 in words is "two billion, one hundred one million, two hundred forty-two thousand, two hundred twenty-one".