21311001332 has 6 divisors (see below), whose sum is σ = 37294252338. Its totient is φ = 10655500664.

The previous prime is 21311001323. The next prime is 21311001337. The reversal of 21311001332 is 23310011312.

It can be written as a sum of positive squares in only one way, i.e., 15355175056 + 5955826276 = 123916^2 + 77174^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21311001332.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21311001337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2663875163 + ... + 2663875170.

It is an arithmetic number, because the mean of its divisors is an integer number (6215708723).

Almost surely, 2^21311001332 is an apocalyptic number.

It is an amenable number.

21311001332 is a deficient number, since it is larger than the sum of its proper divisors (15983251006).

21311001332 is a wasteful number, since it uses less digits than its factorization.

21311001332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5327750337 (or 5327750335 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 17.

Adding to 21311001332 its reverse (23310011312), we get a palindrome (44621012644).

The spelling of 21311001332 in words is "twenty-one billion, three hundred eleven million, one thousand, three hundred thirty-two".