16921924 has 6 divisors (see below), whose sum is σ = 29613374. Its totient is φ = 8460960.

The previous prime is 16921921. The next prime is 16921937. The reversal of 16921924 is 42912961.

It can be written as a sum of positive squares in only one way, i.e., 10771524 + 6150400 = 3282^2 + 2480^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 16921924.

It is not an unprimeable number, because it can be changed into a prime (16921921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2115237 + ... + 2115244.

Almost surely, 2^16921924 is an apocalyptic number.

It is an amenable number.

16921924 is a deficient number, since it is larger than the sum of its proper divisors (12691450).

16921924 is a wasteful number, since it uses less digits than its factorization.

16921924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4230485 (or 4230483 counting only the distinct ones).

The product of its digits is 7776, while the sum is 34.

The square root of 16921924 is about 4113.6266237956. The cubic root of 16921924 is about 256.7339168994.

The spelling of 16921924 in words is "sixteen million, nine hundred twenty-one thousand, nine hundred twenty-four".