21406420640142 has 96 divisors (see below), whose sum is σ = 49347695314944. Its totient is φ = 6683084755200.

The previous prime is 21406420640093. The next prime is 21406420640167. The reversal of 21406420640142 is 24104602460412.

21406420640142 is a `hidden beast` number, since 2 + 1 + 4 + 0 + 6 + 4 + 2 + 0 + 640 + 1 + 4 + 2 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 21406420640097 and 21406420640106.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 714795213 + ... + 714825159.

It is an arithmetic number, because the mean of its divisors is an integer number (514038492864).

Almost surely, 2^{21406420640142} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21406420640142, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24673847657472).

21406420640142 is an abundant number, since it is smaller than the sum of its proper divisors (27941274674802).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21406420640142 is a wasteful number, since it uses less digits than its factorization.

21406420640142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41254 (or 41251 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 36.

The spelling of 21406420640142 in words is "twenty-one trillion, four hundred six billion, four hundred twenty million, six hundred forty thousand, one hundred forty-two".