66555513315 has 24 divisors (see below), whose sum is σ = 122148943488. Its totient is φ = 33408257280.

The previous prime is 66555513263. The next prime is 66555513317. The reversal of 66555513315 is 51331555566.

66555513315 is a `hidden beast` number, since 6 + 6 + 55 + 551 + 33 + 15 = 666.

It is not a de Polignac number, because 66555513315 - 2¹⁰ = 66555512291 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (66555513317) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43499571 + ... + 43501100.

It is an arithmetic number, because the mean of its divisors is an integer number (5089539312).

Almost surely, 2^66555513315 is an apocalyptic number.

66555513315 is a deficient number, since it is larger than the sum of its proper divisors (55593430173).

66555513315 is a wasteful number, since it uses less digits than its factorization.

66555513315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87000699 (or 87000696 counting only the distinct ones).

The product of its digits is 1012500, while the sum is 45.

The spelling of 66555513315 in words is "sixty-six billion, five hundred fifty-five million, five hundred thirteen thousand, three hundred fifteen".