16921836 has 72 divisors (see below), whose sum is σ = 45287424. Its totient is φ = 5316960.

The previous prime is 16921823. The next prime is 16921841. The reversal of 16921836 is 63812961.

It is a super-2 number, since 2×16921836² = 572697067221792, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 16921836.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 88501 + ... + 88691.

It is an arithmetic number, because the mean of its divisors is an integer number (628992).

Almost surely, 2^16921836 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16921836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22643712).

16921836 is an abundant number, since it is smaller than the sum of its proper divisors (28365588).

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

16921836 is a wasteful number, since it uses less digits than its factorization.

16921836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331 (or 326 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 16921836 is about 4113.6159276238. The cubic root of 16921836 is about 256.7334718629.

The spelling of 16921836 in words is "sixteen million, nine hundred twenty-one thousand, eight hundred thirty-six".