21858957120 has 1344 divisors, whose sum is σ = 99676329984. Its totient is φ = 3917168640.

The previous prime is 21858957101. The next prime is 21858957121. The reversal of 21858957120 is 2175985812.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a super-3 number, since 3×21858957120³ (a number of 32 digits) contains 333 as substring.

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 21858957120.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21858957121) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 508347819 + ... + 508347861.

It is an arithmetic number, because the mean of its divisors is an integer number (74163936).

Almost surely, 2^21858957120 is an apocalyptic number.

21858957120 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 21858957120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49838164992).

21858957120 is an abundant number, since it is smaller than the sum of its proper divisors (77817372864).

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

21858957120 is a wasteful number, since it uses less digits than its factorization.

21858957120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 48.

The spelling of 21858957120 in words is "twenty-one billion, eight hundred fifty-eight million, nine hundred fifty-seven thousand, one hundred twenty".