21021123213200 has 240 divisors, whose sum is σ = 58361176413504. Its totient is φ = 7191204249600.

The previous prime is 21021123213143. The next prime is 21021123213253. The reversal of 21021123213200 is 231232112012.

It is a super-2 number, since 2×21021123213200² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 171754427 + ... + 171876773.

Almost surely, 2^{21021123213200} is an apocalyptic number.

21021123213200 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 21021123213200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29180588206752).

21021123213200 is an abundant number, since it is smaller than the sum of its proper divisors (37340053200304).

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

21021123213200 is a wasteful number, since it uses less digits than its factorization.

21021123213200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124690 (or 124679 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 21021123213200 its reverse (231232112012), we get a palindrome (21252355325212).

The spelling of 21021123213200 in words is "twenty-one trillion, twenty-one billion, one hundred twenty-three million, two hundred thirteen thousand, two hundred".