16989945 has 64 divisors (see below), whose sum is σ = 32845824. Its totient is φ = 7338240.

The previous prime is 16989943. The next prime is 16989967. The reversal of 16989945 is 54998961.

It is not a de Polignac number, because 16989945 - 2¹ = 16989943 is a prime.

It is a super-2 number, since 2×16989945² = 577316462206050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (16989941) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 239260 + ... + 239330.

It is an arithmetic number, because the mean of its divisors is an integer number (513216).

Almost surely, 2^16989945 is an apocalyptic number.

16989945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

16989945 is a deficient number, since it is larger than the sum of its proper divisors (15855879).

16989945 is a wasteful number, since it uses less digits than its factorization.

16989945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182.

The product of its digits is 699840, while the sum is 51.

The square root of 16989945 is about 4121.8860974074. The cubic root of 16989945 is about 257.0774544866.

The spelling of 16989945 in words is "sixteen million, nine hundred eighty-nine thousand, nine hundred forty-five".