21002555200 has 168 divisors, whose sum is σ = 56624768640. Its totient is φ = 7603814400.

The previous prime is 21002555183. The next prime is 21002555201. The reversal of 21002555200 is 255520012.

It is a super-2 number, since 2×21002555200² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002555201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4203904 + ... + 4208896.

Almost surely, 2^21002555200 is an apocalyptic number.

21002555200 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 21002555200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28312384320).

21002555200 is an abundant number, since it is smaller than the sum of its proper divisors (35622213440).

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

21002555200 is a wasteful number, since it uses less digits than its factorization.

21002555200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5265 (or 5250 counting only the distinct ones).

The product of its (nonzero) digits is 1000, while the sum is 22.

It can be divided in two parts, 210025 and 55200, that added together give a square (265225 = 515²).

The spelling of 21002555200 in words is "twenty-one billion, two million, five hundred fifty-five thousand, two hundred".