16923021 has 8 divisors (see below), whose sum is σ = 22607904. Its totient is φ = 11260080.

The previous prime is 16923019. The next prime is 16923031. The reversal of 16923021 is 12032961.

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

It is not a de Polignac number, because 16923021 - 2¹ = 16923019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 16922982 and 16923000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16923001) 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, 3591 + ... + 6836.

It is an arithmetic number, because the mean of its divisors is an integer number (2825988).

Almost surely, 2^16923021 is an apocalyptic number.

It is an amenable number.

16923021 is a deficient number, since it is larger than the sum of its proper divisors (5684883).

16923021 is a wasteful number, since it uses less digits than its factorization.

16923021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10971.

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 16923021 is about 4113.7599589670. The cubic root of 16923021 is about 256.7394645551.

Adding to 16923021 its reverse (12032961), we get a palindrome (28955982).

The spelling of 16923021 in words is "sixteen million, nine hundred twenty-three thousand, twenty-one".