665398141 has 4 divisors (see below), whose sum is σ = 666084384. Its totient is φ = 664711900.

The previous prime is 665398109. The next prime is 665398159. The reversal of 665398141 is 141893566.

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, and also an emirpimes, since its reverse is a distinct semiprime: 141893566 = 2 ⋅70946783.

It is a cyclic number.

It is not a de Polignac number, because 665398141 - 2⁵ = 665398109 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 (665398171) 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, 341665 + ... + 343606.

It is an arithmetic number, because the mean of its divisors is an integer number (166521096).

Almost surely, 2^665398141 is an apocalyptic number.

It is an amenable number.

665398141 is a deficient number, since it is larger than the sum of its proper divisors (686243).

665398141 is an equidigital number, since it uses as much as digits as its factorization.

665398141 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 686242.

The product of its digits is 155520, while the sum is 43.

The square root of 665398141 is about 25795.3123842298. The cubic root of 665398141 is about 873.0260333115.

The spelling of 665398141 in words is "six hundred sixty-five million, three hundred ninety-eight thousand, one hundred forty-one".