667651464671 has 4 divisors (see below), whose sum is σ = 690673929000. Its totient is φ = 644629000344.

The previous prime is 667651464659. The next prime is 667651464709. The reversal of 667651464671 is 176464156766.

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 667651464671 - 2⁶ = 667651464607 is a prime.

It is a super-2 number, since 2×667651464671² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 667651464671.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667651404671) 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, 11511232121 + ... + 11511232178.

It is an arithmetic number, because the mean of its divisors is an integer number (172668482250).

Almost surely, 2^667651464671 is an apocalyptic number.

667651464671 is a deficient number, since it is larger than the sum of its proper divisors (23022464329).

667651464671 is a wasteful number, since it uses less digits than its factorization.

667651464671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23022464328.

The product of its digits is 30481920, while the sum is 59.

The spelling of 667651464671 in words is "six hundred sixty-seven billion, six hundred fifty-one million, four hundred sixty-four thousand, six hundred seventy-one".