21220304024 has 8 divisors (see below), whose sum is σ = 39788070060. Its totient is φ = 10610152008.

The previous prime is 21220304003. The next prime is 21220304029. The reversal of 21220304024 is 42040302212.

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 21220303987 and 21220304005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220304029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1326268994 + ... + 1326269009.

Almost surely, 2^21220304024 is an apocalyptic number.

It is an amenable number.

21220304024 is a deficient number, since it is larger than the sum of its proper divisors (18567766036).

21220304024 is a wasteful number, since it uses less digits than its factorization.

21220304024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2652538009 (or 2652538005 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

Adding to 21220304024 its reverse (42040302212), we get a palindrome (63260606236).

The spelling of 21220304024 in words is "twenty-one billion, two hundred twenty million, three hundred four thousand, twenty-four".