665156448 has 240 divisors, whose sum is σ = 2189935440. Its totient is φ = 196300800.

The previous prime is 665156431. The next prime is 665156461. The reversal of 665156448 is 844651566.

665156448 is nontrivially palindromic in base 15.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1168708 + ... + 1169276.

It is an arithmetic number, because the mean of its divisors is an integer number (9124731).

Almost surely, 2^665156448 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665156448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1094967720).

665156448 is an abundant number, since it is smaller than the sum of its proper divisors (1524778992).

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

665156448 is a wasteful number, since it uses less digits than its factorization.

665156448 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 643 (or 626 counting only the distinct ones).

The product of its digits is 691200, while the sum is 45.

The square root of 665156448 is about 25790.6271346782. The cubic root of 665156448 is about 872.9203172392.

The spelling of 665156448 in words is "six hundred sixty-five million, one hundred fifty-six thousand, four hundred forty-eight".