21442303188 has 18 divisors (see below), whose sum is σ = 54201377594. Its totient is φ = 7147434384.

The previous prime is 21442303163. The next prime is 21442303189. The reversal of 21442303188 is 88130324412.

It is a happy number.

21442303188 is a `hidden beast` number, since 2 + 1 + 442 + 30 + 3 + 188 = 666.

It can be written as a sum of positive squares in only one way, i.e., 18084332484 + 3357970704 = 134478^2 + 57948^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×21442303188² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 595619533 = 21442303188 / (2 + 1 + 4 + 4 + 2 + 3 + 0 + 3 + 1 + 8 + 8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21442303189) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 297809731 + ... + 297809802.

Almost surely, 2^21442303188 is an apocalyptic number.

It is an amenable number.

21442303188 is an abundant number, since it is smaller than the sum of its proper divisors (32759074406).

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

21442303188 is a wasteful number, since it uses less digits than its factorization.

21442303188 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 595619543 (or 595619538 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The spelling of 21442303188 in words is "twenty-one billion, four hundred forty-two million, three hundred three thousand, one hundred eighty-eight".