42640315 has 4 divisors (see below), whose sum is σ = 51168384. Its totient is φ = 34112248.

The previous prime is 42640309. The next prime is 42640331. The reversal of 42640315 is 51304624.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42640315 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 42640315.

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, 4264027 + ... + 4264036.

It is an arithmetic number, because the mean of its divisors is an integer number (12792096).

Almost surely, 2^42640315 is an apocalyptic number.

42640315 is a deficient number, since it is larger than the sum of its proper divisors (8528069).

42640315 is an equidigital number, since it uses as much as digits as its factorization.

42640315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8528068.

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 42640315 is about 6529.9552065845. The cubic root of 42640315 is about 349.3602326380.

Adding to 42640315 its reverse (51304624), we get a palindrome (93944939).

The spelling of 42640315 in words is "forty-two million, six hundred forty thousand, three hundred fifteen".