21864605741 has 6 divisors (see below), whose sum is σ = 24032996526. Its totient is φ = 19876914200.

The previous prime is 21864605681. The next prime is 21864605773. The reversal of 21864605741 is 14750646812.

It can be written as a sum of positive squares in only one way, i.e., 21114996100 + 749609641 = 145310^2 + 27379^2 .

It is not a de Polignac number, because 21864605741 - 2¹⁰ = 21864604717 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21864605692 and 21864605701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21864602741) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 90349490 + ... + 90349731.

It is an arithmetic number, because the mean of its divisors is an integer number (4005499421).

Almost surely, 2^21864605741 is an apocalyptic number.

It is an amenable number.

21864605741 is a deficient number, since it is larger than the sum of its proper divisors (2168390785).

21864605741 is a wasteful number, since it uses less digits than its factorization.

21864605741 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180699243 (or 180699232 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 44.

The spelling of 21864605741 in words is "twenty-one billion, eight hundred sixty-four million, six hundred five thousand, seven hundred forty-one".