42388817 has 4 divisors (see below), whose sum is σ = 43188660. Its totient is φ = 41588976.

The previous prime is 42388813. The next prime is 42388859. The reversal of 42388817 is 71888324.

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

It can be written as a sum of positive squares in 2 ways, for example, as 26460736 + 15928081 = 5144^2 + 3991^2 .

It is a cyclic number.

It is not a de Polignac number, because 42388817 - 2² = 42388813 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42388813) 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, 399842 + ... + 399947.

It is an arithmetic number, because the mean of its divisors is an integer number (10797165).

Almost surely, 2^42388817 is an apocalyptic number.

It is an amenable number.

42388817 is a deficient number, since it is larger than the sum of its proper divisors (799843).

42388817 is an equidigital number, since it uses as much as digits as its factorization.

42388817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 799842.

The product of its digits is 86016, while the sum is 41.

The square root of 42388817 is about 6510.6694740249. The cubic root of 42388817 is about 348.6720207801.

The spelling of 42388817 in words is "forty-two million, three hundred eighty-eight thousand, eight hundred seventeen".