65866434491 has 16 divisors (see below), whose sum is σ = 77389236960. Its totient is φ = 55267038720.

The previous prime is 65866434467. The next prime is 65866434581. The reversal of 65866434491 is 19443466856.

It is a cyclic number.

It is not a de Polignac number, because 65866434491 - 2⁶ = 65866434427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65866434401) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2119421 + ... + 2150273.

It is an arithmetic number, because the mean of its divisors is an integer number (4836827310).

Almost surely, 2^65866434491 is an apocalyptic number.

65866434491 is a deficient number, since it is larger than the sum of its proper divisors (11522802469).

65866434491 is a wasteful number, since it uses less digits than its factorization.

65866434491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45806.

The product of its digits is 14929920, while the sum is 56.

The spelling of 65866434491 in words is "sixty-five billion, eight hundred sixty-six million, four hundred thirty-four thousand, four hundred ninety-one".