16765215409 has 2 divisors, whose sum is σ = 16765215410. Its totient is φ = 16765215408.

The previous prime is 16765215371. The next prime is 16765215451. The reversal of 16765215409 is 90451256761.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14596264225 + 2168951184 = 120815^2 + 46572^2 .

It is a cyclic number.

It is not a de Polignac number, because 16765215409 - 2²⁵ = 16731660977 is a prime.

It is not a weakly prime, because it can be changed into another prime (16765215469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8382607704 + 8382607705.

It is an arithmetic number, because the mean of its divisors is an integer number (8382607705).

Almost surely, 2^16765215409 is an apocalyptic number.

It is an amenable number.

16765215409 is a deficient number, since it is larger than the sum of its proper divisors (1).

16765215409 is an equidigital number, since it uses as much as digits as its factorization.

16765215409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 453600, while the sum is 46.

The spelling of 16765215409 in words is "sixteen billion, seven hundred sixty-five million, two hundred fifteen thousand, four hundred nine".