21400342400 has 96 divisors (see below), whose sum is σ = 53360457480. Its totient is φ = 8480000000.

The previous prime is 21400342399. The next prime is 21400342429. The reversal of 21400342400 is 424300412.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 311150 + ... + 373650.

Almost surely, 2^21400342400 is an apocalyptic number.

21400342400 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 21400342400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26680228740).

21400342400 is an abundant number, since it is smaller than the sum of its proper divisors (31960115080).

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

21400342400 is a wasteful number, since it uses less digits than its factorization.

21400342400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62632 (or 62615 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

Adding to 21400342400 its reverse (424300412), we get a palindrome (21824642812).

It can be divided in two parts, 21400 and 342400, that multiplied together give a square (7327360000 = 85600²).

The spelling of 21400342400 in words is "twenty-one billion, four hundred million, three hundred forty-two thousand, four hundred".