21221323102 has 16 divisors (see below), whose sum is σ = 36409332960. Its totient is φ = 9087372288.

The previous prime is 21221323093. The next prime is 21221323103. The reversal of 21221323102 is 20132312212.

It is a self number, because there is not a number n which added to its sum of digits gives 21221323102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221323103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 605727 + ... + 639802.

It is an arithmetic number, because the mean of its divisors is an integer number (2275583310).

Almost surely, 2^21221323102 is an apocalyptic number.

21221323102 is a deficient number, since it is larger than the sum of its proper divisors (15188009858).

21221323102 is a wasteful number, since it uses less digits than its factorization.

21221323102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1246755.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21221323102 its reverse (20132312212), we get a palindrome (41353635314).

The spelling of 21221323102 in words is "twenty-one billion, two hundred twenty-one million, three hundred twenty-three thousand, one hundred two".