21849720144 has 320 divisors, whose sum is σ = 67709952000. Its totient is φ = 6067256832.

The previous prime is 21849720107. The next prime is 21849720157. The reversal of 21849720144 is 44102794812.

It is a super-2 number, since 2×21849720144² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 21849720096 and 21849720105.

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 63 ways as a sum of consecutive naturals, for example, 139170114 + ... + 139170270.

It is an arithmetic number, because the mean of its divisors is an integer number (211593600).

Almost surely, 2^21849720144 is an apocalyptic number.

21849720144 is a gapful number since it is divisible by the number (24) 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 21849720144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33854976000).

21849720144 is an abundant number, since it is smaller than the sum of its proper divisors (45860231856).

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

21849720144 is a wasteful number, since it uses less digits than its factorization.

21849720144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 375 (or 355 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 42.

The spelling of 21849720144 in words is "twenty-one billion, eight hundred forty-nine million, seven hundred twenty thousand, one hundred forty-four".