405921001 has 2 divisors, whose sum is σ = 405921002. Its totient is φ = 405921000.

The previous prime is 405920981. The next prime is 405921007. The reversal of 405921001 is 100129504.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 405619600 + 301401 = 20140^2 + 549^2 .

It is a cyclic number.

It is not a de Polignac number, because 405921001 - 2²³ = 397532393 is a prime.

It is not a weakly prime, because it can be changed into another prime (405921007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202960500 + 202960501.

It is an arithmetic number, because the mean of its divisors is an integer number (202960501).

Almost surely, 2^405921001 is an apocalyptic number.

It is an amenable number.

405921001 is a deficient number, since it is larger than the sum of its proper divisors (1).

405921001 is an equidigital number, since it uses as much as digits as its factorization.

405921001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 405921001 is about 20147.4812569711. The cubic root of 405921001 is about 740.4240332107.

The spelling of 405921001 in words is "four hundred five million, nine hundred twenty-one thousand, one".