21031208583168 has 768 divisors, whose sum is σ = 67934608588800. Its totient is φ = 5764090429440.

The previous prime is 21031208583127. The next prime is 21031208583239. The reversal of 21031208583168 is 86138580213012.

It is a tau number, because it is divible by the number of its divisors (768).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 18964118998 + ... + 18964120106.

It is an arithmetic number, because the mean of its divisors is an integer number (88456521600).

Almost surely, 2^{21031208583168} is an apocalyptic number.

21031208583168 is a gapful number since it is divisible by the number (28) 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 21031208583168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33967304294400).

21031208583168 is an abundant number, since it is smaller than the sum of its proper divisors (46903400005632).

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

21031208583168 is a wasteful number, since it uses less digits than its factorization.

21031208583168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1314 (or 1279 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 48.

The spelling of 21031208583168 in words is "twenty-one trillion, thirty-one billion, two hundred eight million, five hundred eighty-three thousand, one hundred sixty-eight".