42015440 has 20 divisors (see below), whose sum is σ = 97686084. Its totient is φ = 16806144.

The previous prime is 42015433. The next prime is 42015443. The reversal of 42015440 is 4451024.

It can be written as a sum of positive squares in 2 ways, for example, as 22052416 + 19963024 = 4696^2 + 4468^2 .

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

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42015443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 262517 + ... + 262676.

Almost surely, 2^42015440 is an apocalyptic number.

42015440 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

42015440 is an abundant number, since it is smaller than the sum of its proper divisors (55670644).

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

42015440 is a wasteful number, since it uses less digits than its factorization.

42015440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 525206 (or 525200 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 42015440 is about 6481.9318108107. The cubic root of 42015440 is about 347.6452543903.

Adding to 42015440 its reverse (4451024), we get a palindrome (46466464).

The spelling of 42015440 in words is "forty-two million, fifteen thousand, four hundred forty".