240400409 has 2 divisors, whose sum is σ = 240400410. Its totient is φ = 240400408.

The previous prime is 240400309. The next prime is 240400423. The reversal of 240400409 is 904004042.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 181494784 + 58905625 = 13472^2 + 7675^2 .

It is a cyclic number.

It is not a de Polignac number, because 240400409 - 2¹⁶ = 240334873 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (240400429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 120200204 + 120200205.

It is an arithmetic number, because the mean of its divisors is an integer number (120200205).

Almost surely, 2^240400409 is an apocalyptic number.

It is an amenable number.

240400409 is a deficient number, since it is larger than the sum of its proper divisors (1).

240400409 is an equidigital number, since it uses as much as digits as its factorization.

240400409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 240400409 is about 15504.8511440775. The cubic root of 240400409 is about 621.7919102442.

The spelling of 240400409 in words is "two hundred forty million, four hundred thousand, four hundred nine".