451621409 has 2 divisors, whose sum is σ = 451621410. Its totient is φ = 451621408.

The previous prime is 451621403. The next prime is 451621453. The reversal of 451621409 is 904126154.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 238023184 + 213598225 = 15428^2 + 14615^2 .

It is a cyclic number.

It is not a de Polignac number, because 451621409 - 2⁸ = 451621153 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (451621403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 225810704 + 225810705.

It is an arithmetic number, because the mean of its divisors is an integer number (225810705).

Almost surely, 2^451621409 is an apocalyptic number.

It is an amenable number.

451621409 is a deficient number, since it is larger than the sum of its proper divisors (1).

451621409 is an equidigital number, since it uses as much as digits as its factorization.

451621409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 451621409 is about 21251.3860489146. The cubic root of 451621409 is about 767.2287003139.

The spelling of 451621409 in words is "four hundred fifty-one million, six hundred twenty-one thousand, four hundred nine".