664801812601 has 4 divisors (see below), whose sum is σ = 667952532304. Its totient is φ = 661651092900.

The previous prime is 664801812589. The next prime is 664801812613. The reversal of 664801812601 is 106218108466.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (664801812589) and next prime (664801812613).

It is a cyclic number.

It is not a de Polignac number, because 664801812601 - 2⁵ = 664801812569 is a prime.

It is a super-2 number, since 2×664801812601² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664801812641) 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, 1575359535 + ... + 1575359956.

It is an arithmetic number, because the mean of its divisors is an integer number (166988133076).

Almost surely, 2^664801812601 is an apocalyptic number.

It is an amenable number.

664801812601 is a deficient number, since it is larger than the sum of its proper divisors (3150719703).

664801812601 is a wasteful number, since it uses less digits than its factorization.

664801812601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3150719702.

The product of its (nonzero) digits is 110592, while the sum is 43.

The spelling of 664801812601 in words is "six hundred sixty-four billion, eight hundred one million, eight hundred twelve thousand, six hundred one".