21135136000 has 288 divisors, whose sum is σ = 58122529920. Its totient is φ = 7593984000.

The previous prime is 21135135991. The next prime is 21135136027. The reversal of 21135136000 is 63153112.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

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, 34143691 + ... + 34144309.

It is an arithmetic number, because the mean of its divisors is an integer number (201814340).

Almost surely, 2^21135136000 is an apocalyptic number.

21135136000 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 21135136000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29061264960).

21135136000 is an abundant number, since it is smaller than the sum of its proper divisors (36987393920).

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

21135136000 is an equidigital number, since it uses as much as digits as its factorization.

21135136000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 758 (or 734 counting only the distinct ones).

The product of its (nonzero) digits is 540, while the sum is 22.

Adding to 21135136000 its reverse (63153112), we get a palindrome (21198289112).

The spelling of 21135136000 in words is "twenty-one billion, one hundred thirty-five million, one hundred thirty-six thousand".