16561698 has 8 divisors (see below), whose sum is σ = 33123408. Its totient is φ = 5520564.

The previous prime is 16561691. The next prime is 16561703. The reversal of 16561698 is 89616561.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

16561698 is an admirable number.

It is an alternating number because its digits alternate between odd and even.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (16561691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1380136 + ... + 1380147.

It is an arithmetic number, because the mean of its divisors is an integer number (4140426).

Almost surely, 2^16561698 is an apocalyptic number.

16561698 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16561698 is a wasteful number, since it uses less digits than its factorization.

16561698 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2760288.

The product of its digits is 77760, while the sum is 42.

The square root of 16561698 is about 4069.6066148954. The cubic root of 16561698 is about 254.8990911770.

The spelling of 16561698 in words is "sixteen million, five hundred sixty-one thousand, six hundred ninety-eight".