405021623 has 2 divisors, whose sum is σ = 405021624. Its totient is φ = 405021622.

The previous prime is 405021581. The next prime is 405021641. The reversal of 405021623 is 326120504.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 405021623 - 2¹⁸ = 404759479 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (405024623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202510811 + 202510812.

It is an arithmetic number, because the mean of its divisors is an integer number (202510812).

Almost surely, 2^405021623 is an apocalyptic number.

405021623 is a deficient number, since it is larger than the sum of its proper divisors (1).

405021623 is an equidigital number, since it uses as much as digits as its factorization.

405021623 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 405021623 is about 20125.1490180818. The cubic root of 405021623 is about 739.8767892015.

The spelling of 405021623 in words is "four hundred five million, twenty-one thousand, six hundred twenty-three".