21004423041 has 16 divisors (see below), whose sum is σ = 32787393408. Its totient is φ = 11709782400.

The previous prime is 21004423039. The next prime is 21004423043. The reversal of 21004423041 is 14032440012.

It is an interprime number because it is at equal distance from previous prime (21004423039) and next prime (21004423043).

It is not a de Polignac number, because 21004423041 - 2¹ = 21004423039 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21004422999 and 21004423017.

It is not an unprimeable number, because it can be changed into a prime (21004423043) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12196830 + ... + 12198551.

It is an arithmetic number, because the mean of its divisors is an integer number (2049212088).

Almost surely, 2^21004423041 is an apocalyptic number.

21004423041 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21004423041 is a deficient number, since it is larger than the sum of its proper divisors (11782970367).

21004423041 is a wasteful number, since it uses less digits than its factorization.

21004423041 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24395432.

The product of its (nonzero) digits is 768, while the sum is 21.

Adding to 21004423041 its reverse (14032440012), we get a palindrome (35036863053).

The spelling of 21004423041 in words is "twenty-one billion, four million, four hundred twenty-three thousand, forty-one".