21021110122 has 4 divisors (see below), whose sum is σ = 31531665186. Its totient is φ = 10510555060.

The previous prime is 21021110119. The next prime is 21021110129. The reversal of 21021110122 is 22101112012.

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

It can be written as a sum of positive squares in only one way, i.e., 12362993721 + 8658116401 = 111189^2 + 93049^2 .

It is a super-2 number, since 2×21021110122² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21021110129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5255277529 + ... + 5255277532.

Almost surely, 2^21021110122 is an apocalyptic number.

21021110122 is a deficient number, since it is larger than the sum of its proper divisors (10510555064).

21021110122 is a wasteful number, since it uses less digits than its factorization.

21021110122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10510555063.

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

Adding to 21021110122 its reverse (22101112012), we get a palindrome (43122222134).

The spelling of 21021110122 in words is "twenty-one billion, twenty-one million, one hundred ten thousand, one hundred twenty-two".