21520101222 has 20 divisors (see below), whose sum is σ = 48220967916. Its totient is φ = 7173367020.

The previous prime is 21520101193. The next prime is 21520101227. The reversal of 21520101222 is 22210102512.

21520101222 is a `hidden beast` number, since 21 + 520 + 1 + 0 + 122 + 2 = 666.

It is a super-2 number, since 2×21520101222² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21520101195 and 21520101204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21520101227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 66419904 + ... + 66420227.

Almost surely, 2^21520101222 is an apocalyptic number.

21520101222 is an abundant number, since it is smaller than the sum of its proper divisors (26700866694).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21520101222 is a wasteful number, since it uses less digits than its factorization.

21520101222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132840145 (or 132840136 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

Adding to 21520101222 its reverse (22210102512), we get a palindrome (43730203734).

The spelling of 21520101222 in words is "twenty-one billion, five hundred twenty million, one hundred one thousand, two hundred twenty-two".