16721071 has 8 divisors (see below), whose sum is σ = 17186400. Its totient is φ = 16258560.

The previous prime is 16721063. The next prime is 16721087. The reversal of 16721071 is 17012761.

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

It is a cyclic number.

It is not a de Polignac number, because 16721071 - 2³ = 16721063 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16721011) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17535 + ... + 18463.

It is an arithmetic number, because the mean of its divisors is an integer number (2148300).

Almost surely, 2^16721071 is an apocalyptic number.

16721071 is a deficient number, since it is larger than the sum of its proper divisors (465329).

16721071 is an equidigital number, since it uses as much as digits as its factorization.

16721071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1409.

The product of its (nonzero) digits is 588, while the sum is 25.

The square root of 16721071 is about 4089.1406187609. The cubic root of 16721071 is about 255.7141126175.

It can be divided in two parts, 167210 and 71, that added together give a square (167281 = 409²).

The spelling of 16721071 in words is "sixteen million, seven hundred twenty-one thousand, seventy-one".