21264540000 has 720 divisors, whose sum is σ = 80098547760. Its totient is φ = 4928000000.

The previous prime is 21264539969. The next prime is 21264540019. The reversal of 21264540000 is 4546212.

It is a super-2 number, since 2×21264540000² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

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 119 ways as a sum of consecutive naturals, for example, 210539950 + ... + 210540050.

It is an arithmetic number, because the mean of its divisors is an integer number (111247983).

Almost surely, 2^21264540000 is an apocalyptic number.

21264540000 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 21264540000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40049273880).

21264540000 is an abundant number, since it is smaller than the sum of its proper divisors (58834007760).

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

21264540000 is a wasteful number, since it uses less digits than its factorization.

21264540000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185 (or 151 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 24.

The spelling of 21264540000 in words is "twenty-one billion, two hundred sixty-four million, five hundred forty thousand".