20612536865 has 16 divisors (see below), whose sum is σ = 25823000448. Its totient is φ = 15765421056.

The previous prime is 20612536853. The next prime is 20612536909. The reversal of 20612536865 is 56863521602.

It is a cyclic number.

It is not a de Polignac number, because 20612536865 - 2⁴ = 20612536849 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 200582 + ... + 285408.

It is an arithmetic number, because the mean of its divisors is an integer number (1613937528).

Almost surely, 2^20612536865 is an apocalyptic number.

It is an amenable number.

20612536865 is a deficient number, since it is larger than the sum of its proper divisors (5210463583).

20612536865 is a wasteful number, since it uses less digits than its factorization.

20612536865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86968.

The product of its (nonzero) digits is 518400, while the sum is 44.

The spelling of 20612536865 in words is "twenty billion, six hundred twelve million, five hundred thirty-six thousand, eight hundred sixty-five".