21877857120 has 384 divisors, whose sum is σ = 81386726400. Its totient is φ = 4937318400.

The previous prime is 21877857119. The next prime is 21877857161. The reversal of 21877857120 is 2175877812.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 21877857120.

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, 13664320 + ... + 13665920.

It is an arithmetic number, because the mean of its divisors is an integer number (211944600).

Almost surely, 2^21877857120 is an apocalyptic number.

21877857120 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 21877857120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40693363200).

21877857120 is an abundant number, since it is smaller than the sum of its proper divisors (59508869280).

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

21877857120 is a wasteful number, since it uses less digits than its factorization.

21877857120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1723 (or 1701 counting only the distinct ones).

The product of its (nonzero) digits is 439040, while the sum is 48.

The spelling of 21877857120 in words is "twenty-one billion, eight hundred seventy-seven million, eight hundred fifty-seven thousand, one hundred twenty".