21220312014 has 128 divisors (see below), whose sum is σ = 53853880320. Its totient is φ = 6134940000.

The previous prime is 21220312007. The next prime is 21220312021. The reversal of 21220312014 is 41021302212.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21220312007) and next prime (21220312021).

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

It is a congruent number.

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 63 ways as a sum of consecutive naturals, for example, 1299279 + ... + 1315509.

It is an arithmetic number, because the mean of its divisors is an integer number (420733440).

Almost surely, 2^21220312014 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21220312014, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26926940160).

21220312014 is an abundant number, since it is smaller than the sum of its proper divisors (32633568306).

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

21220312014 is a wasteful number, since it uses less digits than its factorization.

21220312014 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16355 (or 16349 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21220312014 its reverse (41021302212), we get a palindrome (62241614226).

The spelling of 21220312014 in words is "twenty-one billion, two hundred twenty million, three hundred twelve thousand, fourteen".