21230135121265 has 32 divisors (see below), whose sum is σ = 29153509228800. Its totient is φ = 14538868706304.

The previous prime is 21230135121253. The next prime is 21230135121287. The reversal of 21230135121265 is 56212153103212.

It is a cyclic number.

It is not a de Polignac number, because 21230135121265 - 2²³ = 21230126732657 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21230135121265.

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, 110140302 + ... + 110332888.

It is an arithmetic number, because the mean of its divisors is an integer number (911047163400).

Almost surely, 2^{21230135121265} is an apocalyptic number.

It is an amenable number.

21230135121265 is a deficient number, since it is larger than the sum of its proper divisors (7923374107535).

21230135121265 is a wasteful number, since it uses less digits than its factorization.

21230135121265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196681.

The product of its (nonzero) digits is 21600, while the sum is 34.

Adding to 21230135121265 its reverse (56212153103212), we get a palindrome (77442288224477).

The spelling of 21230135121265 in words is "twenty-one trillion, two hundred thirty billion, one hundred thirty-five million, one hundred twenty-one thousand, two hundred sixty-five".