21124545424 has 20 divisors (see below), whose sum is σ = 40934652336.
Its totient is φ = 10560764192.
The previous prime is 21124545391. The next prime is 21124545461. The reversal of 21124545424 is 42454542112.
It is a self number, because there is not a number n which added to its sum of digits gives 21124545424.
It is an unprimeable number.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25887 + ... + 207169.
Almost surely, 221124545424 is an apocalyptic number.
It is an amenable number.
21124545424 is a deficient number, since it is larger than the sum of its proper divisors (19810106912).
21124545424 is a wasteful number, since it uses less digits than its factorization.
21124545424 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 188574 (or 188568 counting only the distinct ones).
The product of its digits is 51200, while the sum is 34.
The spelling of 21124545424 in words is "twenty-one billion, one hundred twenty-four million, five hundred forty-five thousand, four hundred twenty-four".