21744036541 has 8 divisors (see below), whose sum is σ = 23025701304. Its totient is φ = 20462661120.

The previous prime is 21744036451. The next prime is 21744036547. The reversal of 21744036541 is 14563044712.

It can be written as a sum of positive squares in 4 ways, for example, as 11714815225 + 10029221316 = 108235^2 + 100146^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21744036541 - 2⁹ = 21744036029 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21744036541.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21744036547) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 93241 + ... + 228433.

It is an arithmetic number, because the mean of its divisors is an integer number (2878212663).

Almost surely, 2^21744036541 is an apocalyptic number.

It is an amenable number.

21744036541 is a deficient number, since it is larger than the sum of its proper divisors (1281664763).

21744036541 is a wasteful number, since it uses less digits than its factorization.

21744036541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144671.

The product of its (nonzero) digits is 80640, while the sum is 37.

The spelling of 21744036541 in words is "twenty-one billion, seven hundred forty-four million, thirty-six thousand, five hundred forty-one".