21850353672 has 128 divisors (see below), whose sum is σ = 63750758400. Its totient is φ = 6111376128.

The previous prime is 21850353667. The next prime is 21850353673. The reversal of 21850353672 is 27635305812.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (21850353673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4333729 + ... + 4338767.

It is an arithmetic number, because the mean of its divisors is an integer number (498052800).

Almost surely, 2^21850353672 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21850353672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31875379200).

21850353672 is an abundant number, since it is smaller than the sum of its proper divisors (41900404728).

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

21850353672 is a wasteful number, since it uses less digits than its factorization.

21850353672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5595 (or 5591 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 42.

The spelling of 21850353672 in words is "twenty-one billion, eight hundred fifty million, three hundred fifty-three thousand, six hundred seventy-two".