21180458572 has 96 divisors (see below), whose sum is σ = 46763881472. Its totient is φ = 8169590016.

The previous prime is 21180458543. The next prime is 21180458573. The reversal of 21180458572 is 27585408112.

It is a super-2 number, since 2×21180458572² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is not an unprimeable number, because it can be changed into a prime (21180458573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13726033 + ... + 13727575.

Almost surely, 2^21180458572 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 21180458572, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23381940736).

21180458572 is an abundant number, since it is smaller than the sum of its proper divisors (25583422900).

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

21180458572 is a wasteful number, since it uses less digits than its factorization.

21180458572 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2487 (or 2485 counting only the distinct ones).

The product of its (nonzero) digits is 179200, while the sum is 43.

The spelling of 21180458572 in words is "twenty-one billion, one hundred eighty million, four hundred fifty-eight thousand, five hundred seventy-two".