42819509 has 2 divisors, whose sum is σ = 42819510. Its totient is φ = 42819508.

The previous prime is 42819433. The next prime is 42819527. The reversal of 42819509 is 90591824.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30217009 + 12602500 = 5497^2 + 3550^2 .

It is a cyclic number.

It is not a de Polignac number, because 42819509 - 2¹² = 42815413 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42816509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21409754 + 21409755.

It is an arithmetic number, because the mean of its divisors is an integer number (21409755).

Almost surely, 2^42819509 is an apocalyptic number.

It is an amenable number.

42819509 is a deficient number, since it is larger than the sum of its proper divisors (1).

42819509 is an equidigital number, since it uses as much as digits as its factorization.

42819509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 42819509 is about 6543.6617424803. The cubic root of 42819509 is about 349.8489388926.

The spelling of 42819509 in words is "forty-two million, eight hundred nineteen thousand, five hundred nine".