165515401409 has 2 divisors, whose sum is σ = 165515401410. Its totient is φ = 165515401408.

The previous prime is 165515401361. The next prime is 165515401417. The reversal of 165515401409 is 904104515561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 152000176384 + 13515225025 = 389872^2 + 116255^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165515401409 is a prime.

It is not a weakly prime, because it can be changed into another prime (165515401609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82757700704 + 82757700705.

It is an arithmetic number, because the mean of its divisors is an integer number (82757700705).

Almost surely, 2^165515401409 is an apocalyptic number.

It is an amenable number.

165515401409 is a deficient number, since it is larger than the sum of its proper divisors (1).

165515401409 is an equidigital number, since it uses as much as digits as its factorization.

165515401409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 108000, while the sum is 41.

The spelling of 165515401409 in words is "one hundred sixty-five billion, five hundred fifteen million, four hundred one thousand, four hundred nine".