21071678342400 has 864 divisors, whose sum is σ = 89424143155200. Its totient is φ = 4755395174400.

The previous prime is 21071678342387. The next prime is 21071678342401. The reversal of 21071678342400 is 424387617012.

21071678342400 is a `hidden beast` number, since 2 + 1 + 0 + 7 + 167 + 83 + 4 + 2 + 400 = 666.

It is a tau number, because it is divible by the number of its divisors (864).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21071678342401) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 95448145 + ... + 95668655.

Almost surely, 2^{21071678342400} is an apocalyptic number.

21071678342400 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 21071678342400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44712071577600).

21071678342400 is an abundant number, since it is smaller than the sum of its proper divisors (68352464812800).

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

21071678342400 is a wasteful number, since it uses less digits than its factorization.

21071678342400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220632 (or 220607 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 45.

The spelling of 21071678342400 in words is "twenty-one trillion, seventy-one billion, six hundred seventy-eight million, three hundred forty-two thousand, four hundred".