21736489489 has 27 divisors (see below), whose sum is σ = 25896525627. Its totient is φ = 18222718800.

The previous prime is 21736489477. The next prime is 21736489517. The reversal of 21736489489 is 98498463712.

The square root of 21736489489 is 147433.

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., 3215457025 + 18521032464 = 56705^2 + 136092^2 .

It is not a de Polignac number, because 21736489489 - 2⁷ = 21736489361 is a prime.

It is a super-2 number, since 2×21736489489² (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 (21736489409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 21082404 + ... + 21083434.

Almost surely, 2^21736489489 is an apocalyptic number.

21736489489 is the 147433-rd square number.

21736489489 is the 73717-th centered octagonal number.

It is an amenable number.

21736489489 is a deficient number, since it is larger than the sum of its proper divisors (4160036138).

21736489489 is an equidigital number, since it uses as much as digits as its factorization.

21736489489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2110 (or 1055 counting only the distinct ones).

The product of its digits is 20901888, while the sum is 61.

It can be divided in two parts, 21736 and 489489, that added together give a square (511225 = 715²).

The spelling of 21736489489 in words is "twenty-one billion, seven hundred thirty-six million, four hundred eighty-nine thousand, four hundred eighty-nine".