66155515505 has 8 divisors (see below), whose sum is σ = 79388180352. Its totient is φ = 52923371248.

The previous prime is 66155515493. The next prime is 66155515571. The reversal of 66155515505 is 50551555166.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66155515505 - 2¹⁴ = 66155499121 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 250802 + ... + 441828.

It is an arithmetic number, because the mean of its divisors is an integer number (9923522544).

Almost surely, 2^66155515505 is an apocalyptic number.

It is an amenable number.

66155515505 is a deficient number, since it is larger than the sum of its proper divisors (13232664847).

66155515505 is a wasteful number, since it uses less digits than its factorization.

66155515505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260295.

The product of its (nonzero) digits is 562500, while the sum is 44.

The spelling of 66155515505 in words is "sixty-six billion, one hundred fifty-five million, five hundred fifteen thousand, five hundred five".