19920388 has 6 divisors (see below), whose sum is σ = 34860686. Its totient is φ = 9960192.

The previous prime is 19920353. The next prime is 19920391. The reversal of 19920388 is 88302991.

It can be written as a sum of positive squares in only one way, i.e., 11614464 + 8305924 = 3408^2 + 2882^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 19920388.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2490045 + ... + 2490052.

Almost surely, 2^19920388 is an apocalyptic number.

It is an amenable number.

19920388 is a deficient number, since it is larger than the sum of its proper divisors (14940298).

19920388 is a wasteful number, since it uses less digits than its factorization.

19920388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4980101 (or 4980099 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 40.

The square root of 19920388 is about 4463.2261874120. The cubic root of 19920388 is about 271.0811156807.

The spelling of 19920388 in words is "nineteen million, nine hundred twenty thousand, three hundred eighty-eight".