21414400020 has 144 divisors (see below), whose sum is σ = 70026378240. Its totient is φ = 5265762048.

The previous prime is 21414400019. The next prime is 21414400027. The reversal of 21414400020 is 2000441412.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21414399966 and 21414400002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21414400027) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2539371 + ... + 2547789.

Almost surely, 2^21414400020 is an apocalyptic number.

21414400020 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 21414400020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35013189120).

21414400020 is an abundant number, since it is smaller than the sum of its proper divisors (48611978220).

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

21414400020 is a wasteful number, since it uses less digits than its factorization.

21414400020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9534 (or 9529 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 21414400020 its reverse (2000441412), we get a palindrome (23414841432).

The spelling of 21414400020 in words is "twenty-one billion, four hundred fourteen million, four hundred thousand, twenty".