16968721 has 8 divisors (see below), whose sum is σ = 21155904. Its totient is φ = 13222320.

The previous prime is 16968719. The next prime is 16968727. The reversal of 16968721 is 12786961.

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 16968721 - 2¹ = 16968719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16968727) 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, 110110 + ... + 110263.

It is an arithmetic number, because the mean of its divisors is an integer number (2644488).

Almost surely, 2^16968721 is an apocalyptic number.

16968721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16968721 is a deficient number, since it is larger than the sum of its proper divisors (4187183).

16968721 is a wasteful number, since it uses less digits than its factorization.

16968721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220391.

The product of its digits is 36288, while the sum is 40.

The square root of 16968721 is about 4119.3107433162. The cubic root of 16968721 is about 256.9703620180.

It can be divided in two parts, 16968 and 721, that added together give a square (17689 = 133²).

The spelling of 16968721 in words is "sixteen million, nine hundred sixty-eight thousand, seven hundred twenty-one".