16561469 has 2 divisors, whose sum is σ = 16561470. Its totient is φ = 16561468.

The previous prime is 16561423. The next prime is 16561507. The reversal of 16561469 is 96416561.

It is an a-pointer prime, because the next prime (16561507) can be obtained adding 16561469 to its sum of digits (38).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14341369 + 2220100 = 3787^2 + 1490^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16561469 is a prime.

It is a super-2 number, since 2×16561469² = 548564510875922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16561169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8280734 + 8280735.

It is an arithmetic number, because the mean of its divisors is an integer number (8280735).

Almost surely, 2^16561469 is an apocalyptic number.

It is an amenable number.

16561469 is a deficient number, since it is larger than the sum of its proper divisors (1).

16561469 is an equidigital number, since it uses as much as digits as its factorization.

16561469 is an evil number, because the sum of its binary digits is even.

The product of its digits is 38880, while the sum is 38.

The square root of 16561469 is about 4069.5784794005. The cubic root of 16561469 is about 254.8979163344.

It can be divided in two parts, 1656 and 1469, that added together give a 5-th power (3125 = 5⁵).

The spelling of 16561469 in words is "sixteen million, five hundred sixty-one thousand, four hundred sixty-nine".