21124744055637 has 16 divisors (see below), whose sum is σ = 28235433485952. Its totient is φ = 14048626003520.

The previous prime is 21124744055621. The next prime is 21124744055683. The reversal of 21124744055637 is 73655044742112.

It is a cyclic number.

It is not a de Polignac number, because 21124744055637 - 2⁴ = 21124744055621 is a prime.

It is a super-2 number, since 2×21124744055637² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21124744055637.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21124744055617) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2712463 + ... + 7043219.

It is an arithmetic number, because the mean of its divisors is an integer number (1764714592872).

Almost surely, 2^{21124744055637} is an apocalyptic number.

It is an amenable number.

21124744055637 is a deficient number, since it is larger than the sum of its proper divisors (7110689430315).

21124744055637 is a wasteful number, since it uses less digits than its factorization.

21124744055637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4334748.

The product of its (nonzero) digits is 5644800, while the sum is 51.

Adding to 21124744055637 its reverse (73655044742112), we get a palindrome (94779788797749).

The spelling of 21124744055637 in words is "twenty-one trillion, one hundred twenty-four billion, seven hundred forty-four million, fifty-five thousand, six hundred thirty-seven".