21151553240000 has 70 divisors (see below), whose sum is σ = 52448977879584. Its totient is φ = 8460621280000.

The previous prime is 21151553239937. The next prime is 21151553240053. The reversal of 21151553240000 is 4235515112.

It is a congruent number.

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 9 ways as a sum of consecutive naturals, for example, 264354416 + ... + 264434415.

Almost surely, 2^{21151553240000} is an apocalyptic number.

21151553240000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21151553240000 is an abundant number, since it is smaller than the sum of its proper divisors (31297424639584).

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

21151553240000 is an frugal number, since it uses more digits than its factorization.

21151553240000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 528788863 (or 528788838 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 29.

Adding to 21151553240000 its reverse (4235515112), we get a palindrome (21155788755112).

The spelling of 21151553240000 in words is "twenty-one trillion, one hundred fifty-one billion, five hundred fifty-three million, two hundred forty thousand".