21220464412 has 48 divisors (see below), whose sum is σ = 44933091840. Its totient is φ = 8565988032.

The previous prime is 21220464337. The next prime is 21220464457. The reversal of 21220464412 is 21446402212.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23248 + ... + 207319.

It is an arithmetic number, because the mean of its divisors is an integer number (936106080).

Almost surely, 2^21220464412 is an apocalyptic number.

It is an amenable number.

21220464412 is an abundant number, since it is smaller than the sum of its proper divisors (23712627428).

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

21220464412 is a wasteful number, since it uses less digits than its factorization.

21220464412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230770 (or 230768 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 28.

Adding to 21220464412 its reverse (21446402212), we get a palindrome (42666866624).

The spelling of 21220464412 in words is "twenty-one billion, two hundred twenty million, four hundred sixty-four thousand, four hundred twelve".