21887418672 has 480 divisors, whose sum is σ = 78384983040. Its totient is φ = 5708206080.

The previous prime is 21887418671. The next prime is 21887418703. The reversal of 21887418672 is 27681478812.

21887418672 is a `hidden beast` number, since 218 + 8 + 7 + 418 + 6 + 7 + 2 = 666.

It is a super-2 number, since 2×21887418672² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21887418671) by changing a digit.

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 95 ways as a sum of consecutive naturals, for example, 70377397 + ... + 70377707.

It is an arithmetic number, because the mean of its divisors is an integer number (163302048).

Almost surely, 2^21887418672 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21887418672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39192491520).

21887418672 is an abundant number, since it is smaller than the sum of its proper divisors (56497564368).

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

21887418672 is a wasteful number, since it uses less digits than its factorization.

21887418672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 426 (or 377 counting only the distinct ones).

The product of its digits is 2408448, while the sum is 54.

The spelling of 21887418672 in words is "twenty-one billion, eight hundred eighty-seven million, four hundred eighteen thousand, six hundred seventy-two".