20878472 has 8 divisors (see below), whose sum is σ = 39147150. Its totient is φ = 10439232.

The previous prime is 20878453. The next prime is 20878477. The reversal of 20878472 is 27487802.

It can be written as a sum of positive squares in only one way, i.e., 16273156 + 4605316 = 4034^2 + 2146^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (20878477) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1304897 + ... + 1304912.

Almost surely, 2^20878472 is an apocalyptic number.

It is an amenable number.

20878472 is a deficient number, since it is larger than the sum of its proper divisors (18268678).

20878472 is a wasteful number, since it uses less digits than its factorization.

20878472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2609815 (or 2609811 counting only the distinct ones).

The product of its (nonzero) digits is 50176, while the sum is 38.

The square root of 20878472 is about 4569.2966636015. The cubic root of 20878472 is about 275.3591868479.

The spelling of 20878472 in words is "twenty million, eight hundred seventy-eight thousand, four hundred seventy-two".