42640440 has 64 divisors (see below), whose sum is σ = 132343200. Its totient is φ = 10977792.

The previous prime is 42640417. The next prime is 42640441. The reversal of 42640440 is 4404624.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 42640440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42640441) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2647 + ... + 9606.

Almost surely, 2^42640440 is an apocalyptic number.

42640440 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

42640440 is an abundant number, since it is smaller than the sum of its proper divisors (89702760).

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

42640440 is a wasteful number, since it uses less digits than its factorization.

42640440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12296 (or 12292 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 24.

The square root of 42640440 is about 6529.9647778529. The cubic root of 42640440 is about 349.3605740206.

The spelling of 42640440 in words is "forty-two million, six hundred forty thousand, four hundred forty".