65491135521 has 32 divisors (see below), whose sum is σ = 100484782848. Its totient is φ = 37165704960.

The previous prime is 65491135519. The next prime is 65491135531. The reversal of 65491135521 is 12553119456.

It is not a de Polignac number, because 65491135521 - 2¹ = 65491135519 is a prime.

It is not an unprimeable number, because it can be changed into a prime (65491135531) 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, 3409075 + ... + 3428231.

It is an arithmetic number, because the mean of its divisors is an integer number (3140149464).

Almost surely, 2^65491135521 is an apocalyptic number.

It is an amenable number.

65491135521 is a deficient number, since it is larger than the sum of its proper divisors (34993647327).

65491135521 is a wasteful number, since it uses less digits than its factorization.

65491135521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20281.

The product of its digits is 162000, while the sum is 42.

The spelling of 65491135521 in words is "sixty-five billion, four hundred ninety-one million, one hundred thirty-five thousand, five hundred twenty-one".