21221222010 has 16 divisors (see below), whose sum is σ = 50930932896. Its totient is φ = 5658992528.

The previous prime is 21221221997. The next prime is 21221222023. The reversal of 21221222010 is 1022212212.

It is an interprime number because it is at equal distance from previous prime (21221221997) and next prime (21221222023).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 353687004 + ... + 353687063.

It is an arithmetic number, because the mean of its divisors is an integer number (3183183306).

Almost surely, 2^21221222010 is an apocalyptic number.

21221222010 is an abundant number, since it is smaller than the sum of its proper divisors (29709710886).

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

21221222010 is a wasteful number, since it uses less digits than its factorization.

21221222010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 707374077.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21221222010 its reverse (1022212212), we get a palindrome (22243434222).

The spelling of 21221222010 in words is "twenty-one billion, two hundred twenty-one million, two hundred twenty-two thousand, ten".