16626640 has 20 divisors (see below), whose sum is σ = 38657124. Its totient is φ = 6650624.

The previous prime is 16626637. The next prime is 16626641. The reversal of 16626640 is 4662661.

It can be written as a sum of positive squares in 2 ways, for example, as 7817616 + 8809024 = 2796^2 + 2968^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16626641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103837 + ... + 103996.

Almost surely, 2^16626640 is an apocalyptic number.

16626640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16626640 is an abundant number, since it is smaller than the sum of its proper divisors (22030484).

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

16626640 is a wasteful number, since it uses less digits than its factorization.

16626640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207846 (or 207840 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 31.

The square root of 16626640 is about 4077.5777123189. The cubic root of 16626640 is about 255.2318281336.

The spelling of 16626640 in words is "sixteen million, six hundred twenty-six thousand, six hundred forty".