40257509 has 2 divisors, whose sum is σ = 40257510. Its totient is φ = 40257508.

The previous prime is 40257487. The next prime is 40257527. The reversal of 40257509 is 90575204.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20205025 + 20052484 = 4495^2 + 4478^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40257509 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 (40257109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20128754 + 20128755.

It is an arithmetic number, because the mean of its divisors is an integer number (20128755).

Almost surely, 2^40257509 is an apocalyptic number.

It is an amenable number.

40257509 is a deficient number, since it is larger than the sum of its proper divisors (1).

40257509 is an equidigital number, since it uses as much as digits as its factorization.

40257509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12600, while the sum is 32.

The square root of 40257509 is about 6344.8805347303. The cubic root of 40257509 is about 342.7275104092.

The spelling of 40257509 in words is "forty million, two hundred fifty-seven thousand, five hundred nine".