16781040 has 160 divisors (see below), whose sum is σ = 61335360. Its totient is φ = 4202496.

The previous prime is 16781033. The next prime is 16781059. The reversal of 16781040 is 4018761.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 16780995 and 16781013.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 36492 + ... + 36948.

It is an arithmetic number, because the mean of its divisors is an integer number (383346).

Almost surely, 2^16781040 is an apocalyptic number.

16781040 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 16781040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30667680).

16781040 is an abundant number, since it is smaller than the sum of its proper divisors (44554320).

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

16781040 is a wasteful number, since it uses less digits than its factorization.

16781040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 496 (or 484 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 16781040 is about 4096.4667702790. The cubic root of 16781040 is about 256.0194483923.

The spelling of 16781040 in words is "sixteen million, seven hundred eighty-one thousand, forty".