16880721 has 48 divisors (see below), whose sum is σ = 28163520. Its totient is φ = 8864640.

The previous prime is 16880707. The next prime is 16880723. The reversal of 16880721 is 12708861.

It is a happy number.

It is not a de Polignac number, because 16880721 - 2¹⁵ = 16847953 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (16880723) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 154815 + ... + 154923.

It is an arithmetic number, because the mean of its divisors is an integer number (586740).

Almost surely, 2^16880721 is an apocalyptic number.

16880721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16880721 is a deficient number, since it is larger than the sum of its proper divisors (11282799).

16880721 is a wasteful number, since it uses less digits than its factorization.

16880721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 33.

The square root of 16880721 is about 4108.6154602250. The cubic root of 16880721 is about 256.5253747188.

The spelling of 16880721 in words is "sixteen million, eight hundred eighty thousand, seven hundred twenty-one".