16447640 has 64 divisors (see below), whose sum is σ = 41796000. Its totient is φ = 5770240.

The previous prime is 16447633. The next prime is 16447657. The reversal of 16447640 is 4674461.

It is a junction number, because it is equal to n+sod(n) for n = 16447597 and 16447606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12116 + ... + 13404.

Almost surely, 2^16447640 is an apocalyptic number.

16447640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16447640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20898000).

16447640 is an abundant number, since it is smaller than the sum of its proper divisors (25348360).

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

16447640 is a wasteful number, since it uses less digits than its factorization.

16447640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1340 (or 1336 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 32.

The square root of 16447640 is about 4055.5690106322. The cubic root of 16447640 is about 254.3125917689.

The spelling of 16447640 in words is "sixteen million, four hundred forty-seven thousand, six hundred forty".