66513515801 has 16 divisors (see below), whose sum is σ = 71403462144. Its totient is φ = 61737425664.

The previous prime is 66513515791. The next prime is 66513515813. The reversal of 66513515801 is 10851531566.

It is a cyclic number.

It is not a de Polignac number, because 66513515801 - 2¹⁰ = 66513514777 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66513515851) 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, 323651 + ... + 487623.

It is an arithmetic number, because the mean of its divisors is an integer number (4462716384).

Almost surely, 2^66513515801 is an apocalyptic number.

It is an amenable number.

66513515801 is a deficient number, since it is larger than the sum of its proper divisors (4889946343).

66513515801 is a wasteful number, since it uses less digits than its factorization.

66513515801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164320.

The product of its (nonzero) digits is 108000, while the sum is 41.

The spelling of 66513515801 in words is "sixty-six billion, five hundred thirteen million, five hundred fifteen thousand, eight hundred one".