665653254 has 16 divisors (see below), whose sum is σ = 1521493248. Its totient is φ = 190186632.

The previous prime is 665653249. The next prime is 665653267. The reversal of 665653254 is 452356566.

It is a Harshad number since it is a multiple of its sum of digits (42), and also a Moran number because the ratio is a prime number: 15848887 = 665653254 / (6 + 6 + 5 + 6 + 5 + 3 + 2 + 5 + 4).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7924402 + ... + 7924485.

It is an arithmetic number, because the mean of its divisors is an integer number (95093328).

Almost surely, 2^665653254 is an apocalyptic number.

665653254 is an abundant number, since it is smaller than the sum of its proper divisors (855839994).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

665653254 is a wasteful number, since it uses less digits than its factorization.

665653254 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15848899.

The product of its digits is 648000, while the sum is 42.

The square root of 665653254 is about 25800.2568591865. The cubic root of 665653254 is about 873.1375914996.

The spelling of 665653254 in words is "six hundred sixty-five million, six hundred fifty-three thousand, two hundred fifty-four".