21584111115842 has 24 divisors (see below), whose sum is σ = 35640864606396. Its totient is φ = 9796116924000.

The previous prime is 21584111115817. The next prime is 21584111115863. The reversal of 21584111115842 is 24851111148512.

It can be written as a sum of positive squares in 2 ways, for example, as 18439131634561 + 3144979481281 = 4294081^2 + 1773409^2 .

It is a super-2 number, since 2×21584111115842² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21584111115793 and 21584111115802.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 67306409 + ... + 67626332.

Almost surely, 2^{21584111115842} is an apocalyptic number.

21584111115842 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21584111115842 is a deficient number, since it is larger than the sum of its proper divisors (14056753490554).

21584111115842 is a wasteful number, since it uses less digits than its factorization.

21584111115842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134933426 (or 134933415 counting only the distinct ones).

The product of its digits is 102400, while the sum is 44.

The spelling of 21584111115842 in words is "twenty-one trillion, five hundred eighty-four billion, one hundred eleven million, one hundred fifteen thousand, eight hundred forty-two".