665025254 has 4 divisors (see below), whose sum is σ = 997537884. Its totient is φ = 332512626.

The previous prime is 665025209. The next prime is 665025259. The reversal of 665025254 is 452520566.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 452520566 = 2 ⋅226260283.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665025259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166256312 + ... + 166256315.

It is an arithmetic number, because the mean of its divisors is an integer number (249384471).

Almost surely, 2^665025254 is an apocalyptic number.

665025254 is a deficient number, since it is larger than the sum of its proper divisors (332512630).

665025254 is a wasteful number, since it uses less digits than its factorization.

665025254 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332512629.

The product of its (nonzero) digits is 72000, while the sum is 35.

The square root of 665025254 is about 25788.0835658643. The cubic root of 665025254 is about 872.8629225022.

The spelling of 665025254 in words is "six hundred sixty-five million, twenty-five thousand, two hundred fifty-four".