21058166400 has 384 divisors, whose sum is σ = 71678745600. Its totient is φ = 5430620160.

The previous prime is 21058166369. The next prime is 21058166417. The reversal of 21058166400 is 466185012.

It is a tau number, because it is divible by the number of its divisors (384).

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, 57379017 + ... + 57379383.

It is an arithmetic number, because the mean of its divisors is an integer number (186663400).

Almost surely, 2^21058166400 is an apocalyptic number.

21058166400 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 21058166400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35839372800).

21058166400 is an abundant number, since it is smaller than the sum of its proper divisors (50620579200).

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

21058166400 is a wasteful number, since it uses less digits than its factorization.

21058166400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 576 (or 559 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 33.

The spelling of 21058166400 in words is "twenty-one billion, fifty-eight million, one hundred sixty-six thousand, four hundred".