21393492664320 has 1792 divisors, whose sum is σ = 92742983424000. Its totient is φ = 4567219568640.

The previous prime is 21393492664307. The next prime is 21393492664409. The reversal of 21393492664320 is 2346629439312.

21393492664320 is a `hidden beast` number, since 2 + 1 + 3 + 9 + 349 + 266 + 4 + 32 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1792).

It is a Harshad number since it is a multiple of its sum of digits (54).

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 127 ways as a sum of consecutive naturals, for example, 19609066975 + ... + 19609068065.

It is an arithmetic number, because the mean of its divisors is an integer number (51753897000).

Almost surely, 2^{21393492664320} is an apocalyptic number.

21393492664320 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 21393492664320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46371491712000).

21393492664320 is an abundant number, since it is smaller than the sum of its proper divisors (71349490759680).

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

21393492664320 is a wasteful number, since it uses less digits than its factorization.

21393492664320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1304 (or 1274 counting only the distinct ones).

The product of its (nonzero) digits is 10077696, while the sum is 54.

The spelling of 21393492664320 in words is "twenty-one trillion, three hundred ninety-three billion, four hundred ninety-two million, six hundred sixty-four thousand, three hundred twenty".