16407816649 has 27 divisors (see below), whose sum is σ = 19798876071. Its totient is φ = 13557363120.

The previous prime is 16407816647. The next prime is 16407816671. The reversal of 16407816649 is 94661870461.

The square root of 16407816649 is 128093.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 8603861049 + 7803955600 = 92757^2 + 88340^2 .

It is not a de Polignac number, because 16407816649 - 2¹ = 16407816647 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16407816596 and 16407816605.

It is not an unprimeable number, because it can be changed into a prime (16407816641) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 26002564 + ... + 26003194.

Almost surely, 2^16407816649 is an apocalyptic number.

16407816649 is the 128093-rd square number.

16407816649 is the 64047-th centered octagonal number.

It is an amenable number.

16407816649 is a deficient number, since it is larger than the sum of its proper divisors (3391059422).

16407816649 is an frugal number, since it uses more digits than its factorization.

16407816649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1334 (or 667 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 52.

The spelling of 16407816649 in words is "sixteen billion, four hundred seven million, eight hundred sixteen thousand, six hundred forty-nine".