2400309 has 6 divisors (see below), whose sum is σ = 3467126. Its totient is φ = 1600200.

The previous prime is 2400283. The next prime is 2400311. The reversal of 2400309 is 9030042.

It can be written as a sum of positive squares in only one way, i.e., 2022084 + 378225 = 1422^2 + 615^2 .

It is not a de Polignac number, because 2400309 - 2⁸ = 2400053 is a prime.

It is a super-2 number, since 2×2400309² = 11522966590962, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2400291 and 2400300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2400329) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 133342 + ... + 133359.

2^2400309 is an apocalyptic number.

It is an amenable number.

2400309 is a deficient number, since it is larger than the sum of its proper divisors (1066817).

2400309 is a wasteful number, since it uses less digits than its factorization.

2400309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266707 (or 266704 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 2400309 is about 1549.2930645943. The cubic root of 2400309 is about 133.8923357360.

The spelling of 2400309 in words is "two million, four hundred thousand, three hundred nine".