421560409 has 2 divisors, whose sum is σ = 421560410. Its totient is φ = 421560408.

The previous prime is 421560383. The next prime is 421560439. The reversal of 421560409 is 904065124.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 419225625 + 2334784 = 20475^2 + 1528^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-421560409 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (421560439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210780204 + 210780205.

It is an arithmetic number, because the mean of its divisors is an integer number (210780205).

Almost surely, 2^421560409 is an apocalyptic number.

It is an amenable number.

421560409 is a deficient number, since it is larger than the sum of its proper divisors (1).

421560409 is an equidigital number, since it uses as much as digits as its factorization.

421560409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 421560409 is about 20531.9363188181. The cubic root of 421560409 is about 749.8135293458.

The spelling of 421560409 in words is "four hundred twenty-one million, five hundred sixty thousand, four hundred nine".