21404430304340 has 96 divisors (see below), whose sum is σ = 45950064048000. Its totient is φ = 8373057707520.

The previous prime is 21404430304337. The next prime is 21404430304343. The reversal of 21404430304340 is 4340303440412.

It is an interprime number because it is at equal distance from previous prime (21404430304337) and next prime (21404430304343).

It is a junction number, because it is equal to n+sod(n) for n = 21404430304297 and 21404430304306.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21404430304343) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 401489606 + ... + 401542914.

It is an arithmetic number, because the mean of its divisors is an integer number (478646500500).

Almost surely, 2^{21404430304340} is an apocalyptic number.

21404430304340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21404430304340 is an abundant number, since it is smaller than the sum of its proper divisors (24545633743660).

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

21404430304340 is a wasteful number, since it uses less digits than its factorization.

21404430304340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55545 (or 55543 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 32.

Adding to 21404430304340 its reverse (4340303440412), we get a palindrome (25744733744752).

The spelling of 21404430304340 in words is "twenty-one trillion, four hundred four billion, four hundred thirty million, three hundred four thousand, three hundred forty".