66570653671 has 4 divisors (see below), whose sum is σ = 68718094144. Its totient is φ = 64423213200.

The previous prime is 66570653659. The next prime is 66570653693. The reversal of 66570653671 is 17635607566.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66570653671 - 2²⁷ = 66436435943 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66570653641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1073720190 + ... + 1073720251.

It is an arithmetic number, because the mean of its divisors is an integer number (17179523536).

Almost surely, 2^66570653671 is an apocalyptic number.

66570653671 is a deficient number, since it is larger than the sum of its proper divisors (2147440473).

66570653671 is a wasteful number, since it uses less digits than its factorization.

66570653671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2147440472.

The product of its (nonzero) digits is 4762800, while the sum is 52.

The spelling of 66570653671 in words is "sixty-six billion, five hundred seventy million, six hundred fifty-three thousand, six hundred seventy-one".