21214036421240 has 128 divisors (see below), whose sum is σ = 51597218453760. Its totient is φ = 7803336013824.

The previous prime is 21214036421203. The next prime is 21214036421317. The reversal of 21214036421240 is 4212463041212.

It is a junction number, because it is equal to n+sod(n) for n = 21214036421197 and 21214036421206.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 450504977 + ... + 450552063.

It is an arithmetic number, because the mean of its divisors is an integer number (403103269170).

Almost surely, 2^{21214036421240} is an apocalyptic number.

21214036421240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21214036421240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25798609226880).

21214036421240 is an abundant number, since it is smaller than the sum of its proper divisors (30383182032520).

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

21214036421240 is a wasteful number, since it uses less digits than its factorization.

21214036421240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50361 (or 50357 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 32.

Adding to 21214036421240 its reverse (4212463041212), we get a palindrome (25426499462452).

The spelling of 21214036421240 in words is "twenty-one trillion, two hundred fourteen billion, thirty-six million, four hundred twenty-one thousand, two hundred forty".