20603444521 has 9 divisors (see below), whose sum is σ = 22648496983. Its totient is φ = 18728968720.

The previous prime is 20603444509. The next prime is 20603444531. The reversal of 20603444521 is 12544430602.

The square root of 20603444521 is 143539.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 11737338921 + 8866105600 = 108339^2 + 94160^2 .

It is not a de Polignac number, because 20603444521 - 2⁹ = 20603444009 is a prime.

It is a super-2 number, since 2×20603444521² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20603444501) by changing a digit.

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 in 8 ways as a sum of consecutive naturals, for example, 1572405 + ... + 1585453.

Almost surely, 2^20603444521 is an apocalyptic number.

20603444521 is the 143539-th square number.

20603444521 is the 71770-th centered octagonal number.

It is an amenable number.

20603444521 is a deficient number, since it is larger than the sum of its proper divisors (2045052462).

20603444521 is an frugal number, since it uses more digits than its factorization.

20603444521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26120 (or 13060 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 31.

It can be divided in two parts, 20603 and 444521, that added together give a square (465124 = 682²).

The spelling of 20603444521 in words is "twenty billion, six hundred three million, four hundred forty-four thousand, five hundred twenty-one".