21031133444 has 24 divisors (see below), whose sum is σ = 38173475928. Its totient is φ = 10130054400.

The previous prime is 21031133411. The next prime is 21031133489. The reversal of 21031133444 is 44433113012.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6217322500 + 14813810944 = 78850^2 + 121712^2 .

It is a super-2 number, since 2×21031133444² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 688529 + ... + 718424.

It is an arithmetic number, because the mean of its divisors is an integer number (1590561497).

Almost surely, 2^21031133444 is an apocalyptic number.

It is an amenable number.

21031133444 is a deficient number, since it is larger than the sum of its proper divisors (17142342484).

21031133444 is a wasteful number, since it uses less digits than its factorization.

21031133444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1407095 (or 1407093 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 26.

Adding to 21031133444 its reverse (44433113012), we get a palindrome (65464246456).

The spelling of 21031133444 in words is "twenty-one billion, thirty-one million, one hundred thirty-three thousand, four hundred forty-four".