66611505665001 has 48 divisors (see below), whose sum is σ = 99897814114560. Its totient is φ = 39430168562400.

The previous prime is 66611505664981. The next prime is 66611505665011. The reversal of 66611505665001 is 10056650511666.

It is not a de Polignac number, because 66611505665001 - 2¹³ = 66611505656809 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66611505665011) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 469119946 + ... + 469261916.

It is an arithmetic number, because the mean of its divisors is an integer number (2081204460720).

Almost surely, 2^{66611505665001} is an apocalyptic number.

It is an amenable number.

66611505665001 is a deficient number, since it is larger than the sum of its proper divisors (33286308449559).

66611505665001 is a wasteful number, since it uses less digits than its factorization.

66611505665001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172098 (or 172087 counting only the distinct ones).

The product of its (nonzero) digits is 972000, while the sum is 48.

The spelling of 66611505665001 in words is "sixty-six trillion, six hundred eleven billion, five hundred five million, six hundred sixty-five thousand, one".