16556545 has 4 divisors (see below), whose sum is σ = 19867860. Its totient is φ = 13245232.

The previous prime is 16556531. The next prime is 16556557. The reversal of 16556545 is 54565561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54565561 = 131 ⋅416531.

It can be written as a sum of positive squares in 2 ways, for example, as 6310144 + 10246401 = 2512^2 + 3201^2 .

It is a cyclic number.

It is not a de Polignac number, because 16556545 - 2⁵ = 16556513 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1655650 + ... + 1655659.

It is an arithmetic number, because the mean of its divisors is an integer number (4966965).

Almost surely, 2^16556545 is an apocalyptic number.

It is an amenable number.

16556545 is a deficient number, since it is larger than the sum of its proper divisors (3311315).

16556545 is an equidigital number, since it uses as much as digits as its factorization.

16556545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3311314.

The product of its digits is 90000, while the sum is 37.

The square root of 16556545 is about 4068.9734577655. The cubic root of 16556545 is about 254.8726520347.

The spelling of 16556545 in words is "sixteen million, five hundred fifty-six thousand, five hundred forty-five".