665050040 has 128 divisors (see below), whose sum is σ = 1615680000. Its totient is φ = 245887488.

The previous prime is 665050039. The next prime is 665050051. The reversal of 665050040 is 40050566.

It is a junction number, because it is equal to n+sod(n) for n = 665049991 and 665050009.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3341861 + ... + 3342059.

It is an arithmetic number, because the mean of its divisors is an integer number (12622500).

Almost surely, 2^665050040 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 665050040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (807840000).

665050040 is an abundant number, since it is smaller than the sum of its proper divisors (950629960).

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

665050040 is a wasteful number, since it uses less digits than its factorization.

665050040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 349 (or 345 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 665050040 is about 25788.5641321885. The cubic root of 665050040 is about 872.8737664571.

The spelling of 665050040 in words is "six hundred sixty-five million, fifty thousand, forty".