21675304180 has 24 divisors (see below), whose sum is σ = 45520975080. Its totient is φ = 8669581440.

The previous prime is 21675304171. The next prime is 21675304187. The reversal of 21675304180 is 8140357612.

It can be written as a sum of positive squares in 4 ways, for example, as 2968724196 + 18706579984 = 54486^2 + 136772^2 .

It is a super-2 number, since 2×21675304180² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21675304187) 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 7 ways as a sum of consecutive naturals, for example, 504586 + ... + 545854.

It is an arithmetic number, because the mean of its divisors is an integer number (1896707295).

Almost surely, 2^21675304180 is an apocalyptic number.

21675304180 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21675304180 is an abundant number, since it is smaller than the sum of its proper divisors (23845670900).

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

21675304180 is a wasteful number, since it uses less digits than its factorization.

21675304180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67539 (or 67537 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 37.

The spelling of 21675304180 in words is "twenty-one billion, six hundred seventy-five million, three hundred four thousand, one hundred eighty".