21421100160 has 512 divisors, whose sum is σ = 78586675200. Its totient is φ = 5511131136.

The previous prime is 21421100143. The next prime is 21421100167. The reversal of 21421100160 is 6100112412.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21421100167) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 94365967 + ... + 94366193.

It is an arithmetic number, because the mean of its divisors is an integer number (153489600).

Almost surely, 2^21421100160 is an apocalyptic number.

21421100160 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 21421100160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39293337600).

21421100160 is an abundant number, since it is smaller than the sum of its proper divisors (57165575040).

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

21421100160 is a wasteful number, since it uses less digits than its factorization.

21421100160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 425 (or 407 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

Adding to 21421100160 its reverse (6100112412), we get a palindrome (27521212572).

The spelling of 21421100160 in words is "twenty-one billion, four hundred twenty-one million, one hundred thousand, one hundred sixty".