21503065566145 has 32 divisors (see below), whose sum is σ = 27269255088000. Its totient is φ = 16232680558080.

The previous prime is 21503065566127. The next prime is 21503065566161. The reversal of 21503065566145 is 54166556030512.

It is a happy number.

It is not a de Polignac number, because 21503065566145 - 2⁴¹ = 19304042310593 is a prime.

It is a super-2 number, since 2×21503065566145² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27007411 + ... + 27792199.

It is an arithmetic number, because the mean of its divisors is an integer number (852164221500).

Almost surely, 2^{21503065566145} is an apocalyptic number.

It is an amenable number.

21503065566145 is a deficient number, since it is larger than the sum of its proper divisors (5766189521855).

21503065566145 is a wasteful number, since it uses less digits than its factorization.

21503065566145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 785953.

The product of its (nonzero) digits is 3240000, while the sum is 49.

The spelling of 21503065566145 in words is "twenty-one trillion, five hundred three billion, sixty-five million, five hundred sixty-six thousand, one hundred forty-five".