16646645 has 8 divisors (see below), whose sum is σ = 19997880. Its totient is φ = 13302720.

The previous prime is 16646639. The next prime is 16646657. The reversal of 16646645 is 54664661.

It can be written as a sum of positive squares in 4 ways, for example, as 790321 + 15856324 = 889^2 + 3982^2 .

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

It is a de Polignac number, because none of the positive numbers 2^k-16646645 is a prime.

It is a super-2 number, since 2×16646645² = 554221579512050, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 16646599 and 16646608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8015 + ... + 9875.

It is an arithmetic number, because the mean of its divisors is an integer number (2499735).

Almost surely, 2^16646645 is an apocalyptic number.

It is an amenable number.

16646645 is a deficient number, since it is larger than the sum of its proper divisors (3351235).

16646645 is a wasteful number, since it uses less digits than its factorization.

16646645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3655.

The product of its digits is 103680, while the sum is 38.

The square root of 16646645 is about 4080.0300243993. The cubic root of 16646645 is about 255.3341511986.

The spelling of 16646645 in words is "sixteen million, six hundred forty-six thousand, six hundred forty-five".