409599991 has 2 divisors, whose sum is σ = 409599992. Its totient is φ = 409599990.

The previous prime is 409599979. The next prime is 409600001. The reversal of 409599991 is 199995904.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 409599991 - 2¹⁹ = 409075703 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (409599901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 204799995 + 204799996.

It is an arithmetic number, because the mean of its divisors is an integer number (204799996).

Almost surely, 2^409599991 is an apocalyptic number.

409599991 is a deficient number, since it is larger than the sum of its proper divisors (1).

409599991 is an equidigital number, since it uses as much as digits as its factorization.

409599991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1180980, while the sum is 55.

The square root of 409599991 is about 20238.5768027300. The cubic root of 409599991 is about 742.6542079387.

It can be divided in two parts, 40959999 and 1, that added together give a 4-th power (40960000 = 80⁴).

The spelling of 409599991 in words is "four hundred nine million, five hundred ninety-nine thousand, nine hundred ninety-one".