16821792 has 72 divisors (see below), whose sum is σ = 51528204. Its totient is φ = 5174784.

The previous prime is 16821781. The next prime is 16821793. The reversal of 16821792 is 29712861.

It can be written as a sum of positive squares in 2 ways, for example, as 16353936 + 467856 = 4044^2 + 684^2 .

It is a tau number, because it is divible by the number of its divisors (72).

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

It is not an unprimeable number, because it can be changed into a prime (16821793) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1498 + ... + 5990.

Almost surely, 2^16821792 is an apocalyptic number.

16821792 is a gapful number since it is divisible by the number (12) 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 16821792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25764102).

16821792 is an abundant number, since it is smaller than the sum of its proper divisors (34706412).

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

16821792 is a wasteful number, since it uses less digits than its factorization.

16821792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4522 (or 4511 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 16821792 is about 4101.4377966757. The cubic root of 16821792 is about 256.2265247581.

The spelling of 16821792 in words is "sixteen million, eight hundred twenty-one thousand, seven hundred ninety-two".