21382920441 has 27 divisors (see below), whose sum is σ = 31333140111. Its totient is φ = 14052021984.

The previous prime is 21382920421. The next prime is 21382920457. The reversal of 21382920441 is 14402928312.

The square root of 21382920441 is 146229.

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., 619263225 + 20763657216 = 24885^2 + 144096^2 .

It is a de Polignac number, because none of the positive numbers 2^k-21382920441 is a prime.

It is a super-2 number, since 2×21382920441² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21382920396 and 21382920405.

It is not an unprimeable number, because it can be changed into a prime (21382920421) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 34655965 + ... + 34656581.

Almost surely, 2^21382920441 is an apocalyptic number.

21382920441 is the 146229-th square number.

21382920441 is the 73115-th centered octagonal number.

It is an amenable number.

21382920441 is a deficient number, since it is larger than the sum of its proper divisors (9950219670).

21382920441 is an frugal number, since it uses more digits than its factorization.

21382920441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1398 (or 699 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

Multiplying 21382920441 by its sum of digits (36), we get a square (769785135876 = 877374²).

It can be divided in two parts, 213829 and 20441, that added together give a triangular number (234270 = T₆₈₄).

The spelling of 21382920441 in words is "twenty-one billion, three hundred eighty-two million, nine hundred twenty thousand, four hundred forty-one".