100402409 has 2 divisors, whose sum is σ = 100402410. Its totient is φ = 100402408.

The previous prime is 100402369. The next prime is 100402411. The reversal of 100402409 is 904204001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 99940009 + 462400 = 9997^2 + 680^2 .

It is a cyclic number.

It is not a de Polignac number, because 100402409 - 2¹² = 100398313 is a prime.

It is a Sophie Germain prime.

Together with 100402411, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (100402499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50201204 + 50201205.

It is an arithmetic number, because the mean of its divisors is an integer number (50201205).

Almost surely, 2^100402409 is an apocalyptic number.

It is an amenable number.

100402409 is a deficient number, since it is larger than the sum of its proper divisors (1).

100402409 is an equidigital number, since it uses as much as digits as its factorization.

100402409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 100402409 is about 10020.1002489995. The cubic root of 100402409 is about 464.7806557898.

The spelling of 100402409 in words is "one hundred million, four hundred two thousand, four hundred nine".