21311003552 has 12 divisors (see below), whose sum is σ = 41956038306. Its totient is φ = 10655501760.

The previous prime is 21311003543. The next prime is 21311003563. The reversal of 21311003552 is 25530011312.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 18759137296 + 2551866256 = 136964^2 + 50516^2 .

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 as a sum of consecutive naturals, namely, 332984399 + ... + 332984462.

Almost surely, 2^21311003552 is an apocalyptic number.

It is an amenable number.

21311003552 is a deficient number, since it is larger than the sum of its proper divisors (20645034754).

21311003552 is an equidigital number, since it uses as much as digits as its factorization.

21311003552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 665968871 (or 665968863 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 23.

Adding to 21311003552 its reverse (25530011312), we get a palindrome (46841014864).

The spelling of 21311003552 in words is "twenty-one billion, three hundred eleven million, three thousand, five hundred fifty-two".