16745561 has 16 divisors (see below), whose sum is σ = 20465280. Its totient is φ = 13374720.

The previous prime is 16745513. The next prime is 16745609. The reversal of 16745561 is 16554761.

It is an interprime number because it is at equal distance from previous prime (16745513) and next prime (16745609).

It is a cyclic number.

It is not a de Polignac number, because 16745561 - 2²² = 12551257 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16745501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12326 + ... + 13616.

It is an arithmetic number, because the mean of its divisors is an integer number (1279080).

Almost surely, 2^16745561 is an apocalyptic number.

It is an amenable number.

16745561 is a deficient number, since it is larger than the sum of its proper divisors (3719719).

16745561 is a wasteful number, since it uses less digits than its factorization.

16745561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1424.

The product of its digits is 25200, while the sum is 35.

The square root of 16745561 is about 4092.1340398379. The cubic root of 16745561 is about 255.8388929768.

It can be divided in two parts, 16745 and 561, that multiplied together give a triangular number (9393945 = T₄₃₃₄).

The spelling of 16745561 in words is "sixteen million, seven hundred forty-five thousand, five hundred sixty-one".