21151241717760 has 5760 divisors, whose sum is σ = 107174189041920. Its totient is φ = 3956680949760.

The previous prime is 21151241717713. The next prime is 21151241717803. The reversal of 21151241717760 is 6771714215112.

21151241717760 is a `hidden beast` number, since 2 + 1 + 1 + 5 + 1 + 2 + 417 + 177 + 60 = 666.

It is a tau number, because it is divible by the number of its divisors (5760).

It is a super-2 number, since 2×21151241717760² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 479 ways as a sum of consecutive naturals, for example, 919619205109 + ... + 919619205131.

It is an arithmetic number, because the mean of its divisors is an integer number (18606630042).

Almost surely, 2^{21151241717760} is an apocalyptic number.

21151241717760 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 21151241717760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53587094520960).

21151241717760 is an abundant number, since it is smaller than the sum of its proper divisors (86022947324160).

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

21151241717760 is a wasteful number, since it uses less digits than its factorization.

21151241717760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126 (or 68 counting only the distinct ones).

The product of its (nonzero) digits is 164640, while the sum is 45.

The spelling of 21151241717760 in words is "twenty-one trillion, one hundred fifty-one billion, two hundred forty-one million, seven hundred seventeen thousand, seven hundred sixty".