21021122 has 8 divisors (see below), whose sum is σ = 31581372. Its totient is φ = 10494000.

The previous prime is 21021107. The next prime is 21021127. The reversal of 21021122 is 22112012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 16008001 + 5013121 = 4001^2 + 2239^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21021127) 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, 6629 + ... + 9272.

Almost surely, 2^21021122 is an apocalyptic number.

21021122 is a deficient number, since it is larger than the sum of its proper divisors (10560250).

21021122 is a wasteful number, since it uses less digits than its factorization.

21021122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16564.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 21021122 is about 4584.8797148889. The cubic root of 21021122 is about 275.9848850506.

Adding to 21021122 its reverse (22112012), we get a palindrome (43133134).

The spelling of 21021122 in words is "twenty-one million, twenty-one thousand, one hundred twenty-two".