2121615554065 has 32 divisors (see below), whose sum is σ = 3096762589440. Its totient is φ = 1362149720064.

The previous prime is 2121615554063. The next prime is 2121615554141. The reversal of 2121615554065 is 5604555161212.

It is not a de Polignac number, because 2121615554065 - 2¹ = 2121615554063 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2121615554063) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9122835 + ... + 9352504.

It is an arithmetic number, because the mean of its divisors is an integer number (96773830920).

Almost surely, 2^{2121615554065} is an apocalyptic number.

It is an amenable number.

2121615554065 is a deficient number, since it is larger than the sum of its proper divisors (975147035375).

2121615554065 is a wasteful number, since it uses less digits than its factorization.

2121615554065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18475561.

The product of its (nonzero) digits is 360000, while the sum is 43.

The spelling of 2121615554065 in words is "two trillion, one hundred twenty-one billion, six hundred fifteen million, five hundred fifty-four thousand, sixty-five".