21004424001 has 72 divisors (see below), whose sum is σ = 35389946592. Its totient is φ = 11954131200.

The previous prime is 21004423991. The next prime is 21004424009. The reversal of 21004424001 is 10042440012.

It is not a de Polignac number, because 21004424001 - 2⁵ = 21004423969 is a prime.

It is a super-2 number, since 2×21004424001² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21004424009) 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 71 ways as a sum of consecutive naturals, for example, 10569930 + ... + 10571916.

It is an arithmetic number, because the mean of its divisors is an integer number (491527036).

Almost surely, 2^21004424001 is an apocalyptic number.

It is an amenable number.

21004424001 is a deficient number, since it is larger than the sum of its proper divisors (14385522591).

21004424001 is a wasteful number, since it uses less digits than its factorization.

21004424001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2603 (or 2589 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 21004424001 its reverse (10042440012), we get a palindrome (31046864013).

The spelling of 21004424001 in words is "twenty-one billion, four million, four hundred twenty-four thousand, one".