21224403352 has 8 divisors (see below), whose sum is σ = 39795756300. Its totient is φ = 10612201672.

The previous prime is 21224403341. The next prime is 21224403353. The reversal of 21224403352 is 25330442212.

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 21224403352.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21224403353) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1326525202 + ... + 1326525217.

Almost surely, 2^21224403352 is an apocalyptic number.

It is an amenable number.

21224403352 is a deficient number, since it is larger than the sum of its proper divisors (18571352948).

21224403352 is a wasteful number, since it uses less digits than its factorization.

21224403352 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2653050425 (or 2653050421 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 28.

Adding to 21224403352 its reverse (25330442212), we get a palindrome (46554845564).

The spelling of 21224403352 in words is "twenty-one billion, two hundred twenty-four million, four hundred three thousand, three hundred fifty-two".