21020122 has 4 divisors (see below), whose sum is σ = 31530186. Its totient is φ = 10510060.

The previous prime is 21020119. The next prime is 21020159. The reversal of 21020122 is 22102012.

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., 19000881 + 2019241 = 4359^2 + 1421^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21020099 and 21020108.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5255029 + ... + 5255032.

Almost surely, 2^21020122 is an apocalyptic number.

21020122 is a deficient number, since it is larger than the sum of its proper divisors (10510064).

21020122 is a wasteful number, since it uses less digits than its factorization.

21020122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10510063.

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 21020122 is about 4584.7706594769. The cubic root of 21020122 is about 275.9805086704.

Adding to 21020122 its reverse (22102012), we get a palindrome (43122134).

It can be divided in two parts, 2102012 and 2, that multiplied together give a palindrome (4204024).

The spelling of 21020122 in words is "twenty-one million, twenty thousand, one hundred twenty-two".