21552403012444 has 24 divisors (see below), whose sum is σ = 38594066919408. Its totient is φ = 10525529723520.

The previous prime is 21552403012249. The next prime is 21552403012453. The reversal of 21552403012444 is 44421030425512.

It is a super-2 number, since 2×21552403012444² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

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, 44187984 + ... + 44673064.

It is an arithmetic number, because the mean of its divisors is an integer number (1608086121642).

Almost surely, 2^{21552403012444} is an apocalyptic number.

It is an amenable number.

21552403012444 is a deficient number, since it is larger than the sum of its proper divisors (17041663906964).

21552403012444 is a wasteful number, since it uses less digits than its factorization.

21552403012444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 743445 (or 743443 counting only the distinct ones).

The product of its (nonzero) digits is 153600, while the sum is 37.

Adding to 21552403012444 its reverse (44421030425512), we get a palindrome (65973433437956).

The spelling of 21552403012444 in words is "twenty-one trillion, five hundred fifty-two billion, four hundred three million, twelve thousand, four hundred forty-four".