19426409 has 2 divisors, whose sum is σ = 19426410. Its totient is φ = 19426408.

The previous prime is 19426397. The next prime is 19426423. The reversal of 19426409 is 90462491.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19386409 + 40000 = 4403^2 + 200^2 .

It is a cyclic number.

It is not a de Polignac number, because 19426409 - 2²⁴ = 2649193 is a prime.

It is not a weakly prime, because it can be changed into another prime (19426439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9713204 + 9713205.

It is an arithmetic number, because the mean of its divisors is an integer number (9713205).

Almost surely, 2^19426409 is an apocalyptic number.

It is an amenable number.

19426409 is a deficient number, since it is larger than the sum of its proper divisors (1).

19426409 is an equidigital number, since it uses as much as digits as its factorization.

19426409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 19426409 is about 4407.5400168348. The cubic root of 19426409 is about 268.8216088971.

The spelling of 19426409 in words is "nineteen million, four hundred twenty-six thousand, four hundred nine".