1985801856065 has 16 divisors (see below), whose sum is σ = 2388148697088. Its totient is φ = 1585186664256.

The previous prime is 1985801856053. The next prime is 1985801856107. The reversal of 1985801856065 is 5606581085891.

It is a cyclic number.

It is not a de Polignac number, because 1985801856065 - 2²² = 1985797661761 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1985801855989 and 1985801856007.

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, 5485664 + ... + 5836446.

It is an arithmetic number, because the mean of its divisors is an integer number (149259293568).

Almost surely, 2^{1985801856065} is an apocalyptic number.

It is an amenable number.

1985801856065 is a deficient number, since it is larger than the sum of its proper divisors (402346841023).

1985801856065 is a wasteful number, since it uses less digits than its factorization.

1985801856065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 353248.

The product of its (nonzero) digits is 20736000, while the sum is 62.

The spelling of 1985801856065 in words is "one trillion, nine hundred eighty-five billion, eight hundred one million, eight hundred fifty-six thousand, sixty-five".