21057013004365 has 24 divisors (see below), whose sum is σ = 28801744374240. Its totient is φ = 14731383985344.

The previous prime is 21057013004359. The next prime is 21057013004369. The reversal of 21057013004365 is 56340031075012.

It is not a de Polignac number, because 21057013004365 - 2⁵ = 21057013004333 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21057013004369) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 655761367 + ... + 655793476.

It is an arithmetic number, because the mean of its divisors is an integer number (1200072682260).

Almost surely, 2^{21057013004365} is an apocalyptic number.

It is an amenable number.

21057013004365 is a deficient number, since it is larger than the sum of its proper divisors (7744731369875).

21057013004365 is a wasteful number, since it uses less digits than its factorization.

21057013004365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1311554893 (or 1311554880 counting only the distinct ones).

The product of its (nonzero) digits is 75600, while the sum is 37.

Adding to 21057013004365 its reverse (56340031075012), we get a palindrome (77397044079377).

The spelling of 21057013004365 in words is "twenty-one trillion, fifty-seven billion, thirteen million, four thousand, three hundred sixty-five".