21260542401364 has 72 divisors (see below), whose sum is σ = 44167727860200. Its totient is φ = 8926528472064.

The previous prime is 21260542401277. The next prime is 21260542401377. The reversal of 21260542401364 is 46310424506212.

It can be written as a sum of positive squares in 4 ways, for example, as 6985616400 + 21253556784964 = 83580^2 + 4610158^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2854417 + ... + 7118200.

It is an arithmetic number, because the mean of its divisors is an integer number (613440664725).

Almost surely, 2^{21260542401364} is an apocalyptic number.

It is an amenable number.

21260542401364 is an abundant number, since it is smaller than the sum of its proper divisors (22907185458836).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21260542401364 is a wasteful number, since it uses less digits than its factorization.

21260542401364 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9972857 (or 9972848 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 40.

Adding to 21260542401364 its reverse (46310424506212), we get a palindrome (67570966907576).

The spelling of 21260542401364 in words is "twenty-one trillion, two hundred sixty billion, five hundred forty-two million, four hundred one thousand, three hundred sixty-four".