42668240 has 20 divisors (see below), whose sum is σ = 99203844. Its totient is φ = 17067264.

The previous prime is 42668207. The next prime is 42668257. The reversal of 42668240 is 4286624.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 10086976 + 32581264 = 3176^2 + 5708^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 42668197 and 42668206.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 266597 + ... + 266756.

Almost surely, 2^42668240 is an apocalyptic number.

42668240 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

42668240 is an abundant number, since it is smaller than the sum of its proper divisors (56535604).

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

42668240 is a wasteful number, since it uses less digits than its factorization.

42668240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 533366 (or 533360 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 32.

The square root of 42668240 is about 6532.0930795573. The cubic root of 42668240 is about 349.4364809457.

The spelling of 42668240 in words is "forty-two million, six hundred sixty-eight thousand, two hundred forty".