21311015542401 has 96 divisors (see below), whose sum is σ = 33780216960000. Its totient is φ = 11864673423360.

The previous prime is 21311015542393. The next prime is 21311015542489. The reversal of 21311015542401 is 10424551011312.

It is not a de Polignac number, because 21311015542401 - 2³ = 21311015542393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21311015542001) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 51856075 + ... + 52265423.

It is an arithmetic number, because the mean of its divisors is an integer number (351877260000).

Almost surely, 2^{21311015542401} is an apocalyptic number.

It is an amenable number.

21311015542401 is a deficient number, since it is larger than the sum of its proper divisors (12469201417599).

21311015542401 is a wasteful number, since it uses less digits than its factorization.

21311015542401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409579 (or 409562 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 30.

Adding to 21311015542401 its reverse (10424551011312), we get a palindrome (31735566553713).

The spelling of 21311015542401 in words is "twenty-one trillion, three hundred eleven billion, fifteen million, five hundred forty-two thousand, four hundred one".