815145066661 has 16 divisors (see below), whose sum is σ = 831178051200. Its totient is φ = 799187378688.

The previous prime is 815145066607. The next prime is 815145066709. The reversal of 815145066661 is 166660541518.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-815145066661 is a prime.

It is a super-2 number, since 2×815145066661² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (815145066761) 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, 113859400 + ... + 113866558.

It is an arithmetic number, because the mean of its divisors is an integer number (51948628200).

Almost surely, 2^815145066661 is an apocalyptic number.

It is an amenable number.

815145066661 is a deficient number, since it is larger than the sum of its proper divisors (16032984539).

815145066661 is a wasteful number, since it uses less digits than its factorization.

815145066661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12108.

The product of its (nonzero) digits is 1036800, while the sum is 49.

The spelling of 815145066661 in words is "eight hundred fifteen billion, one hundred forty-five million, sixty-six thousand, six hundred sixty-one".