20987282 has 8 divisors (see below), whose sum is σ = 33332796. Its totient is φ = 9876352.

The previous prime is 20987269. The next prime is 20987287. The reversal of 20987282 is 28278902.

It can be written as a sum of positive squares in 2 ways, for example, as 19882681 + 1104601 = 4459^2 + 1051^2 .

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

It is not an unprimeable number, because it can be changed into a prime (20987287) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 308603 + ... + 308670.

Almost surely, 2^20987282 is an apocalyptic number.

20987282 is a deficient number, since it is larger than the sum of its proper divisors (12345514).

20987282 is a wasteful number, since it uses less digits than its factorization.

20987282 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 617292.

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 20987282 is about 4581.1878372317. The cubic root of 20987282 is about 275.8367111566.

The spelling of 20987282 in words is "twenty million, nine hundred eighty-seven thousand, two hundred eighty-two".