21520404401041 has 64 divisors (see below), whose sum is σ = 28374099296256. Its totient is φ = 15856823980800.

The previous prime is 21520404401017. The next prime is 21520404401071. The reversal of 21520404401041 is 14010440402512.

It is a happy number.

It is not a de Polignac number, because 21520404401041 - 2¹³ = 21520404392849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21520404401071) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 18216171 + ... + 19361551.

It is an arithmetic number, because the mean of its divisors is an integer number (443345301504).

Almost surely, 2^{21520404401041} is an apocalyptic number.

It is an amenable number.

21520404401041 is a deficient number, since it is larger than the sum of its proper divisors (6853694895215).

21520404401041 is a wasteful number, since it uses less digits than its factorization.

21520404401041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1145662.

The product of its (nonzero) digits is 5120, while the sum is 28.

Adding to 21520404401041 its reverse (14010440402512), we get a palindrome (35530844803553).

The spelling of 21520404401041 in words is "twenty-one trillion, five hundred twenty billion, four hundred four million, four hundred one thousand, forty-one".