21134131200 has 1350 divisors, whose sum is σ = 98081395566. Its totient is φ = 4459069440.

The previous prime is 21134131171. The next prime is 21134131211. The reversal of 21134131200 is 213143112.

21134131200 is a `hidden beast` number, since 2 + 11 + 341 + 312 + 0 + 0 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 65028096 + 21069103104 = 8064^2 + 145152^2 .

It is a tau number, because it is divible by the number of its divisors (1350).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 89 ways as a sum of consecutive naturals, for example, 1625702394 + ... + 1625702406.

Almost surely, 2^21134131200 is an apocalyptic number.

21134131200 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 21134131200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49040697783).

21134131200 is an abundant number, since it is smaller than the sum of its proper divisors (76947264366).

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

21134131200 is an equidigital number, since it uses as much as digits as its factorization.

21134131200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77 (or 30 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21134131200 its reverse (213143112), we get a palindrome (21347274312).

The spelling of 21134131200 in words is "twenty-one billion, one hundred thirty-four million, one hundred thirty-one thousand, two hundred".