20887418 has 8 divisors (see below), whose sum is σ = 31453812. Its totient is φ = 10402816.

The previous prime is 20887393. The next prime is 20887423. The reversal of 20887418 is 81478802.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20857489 + 29929 = 4567^2 + 173^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19805 + ... + 20832.

Almost surely, 2^20887418 is an apocalyptic number.

20887418 is a deficient number, since it is larger than the sum of its proper divisors (10566394).

20887418 is a wasteful number, since it uses less digits than its factorization.

20887418 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40896.

The product of its (nonzero) digits is 28672, while the sum is 38.

The square root of 20887418 is about 4570.2754840381. The cubic root of 20887418 is about 275.3985098331.

The spelling of 20887418 in words is "twenty million, eight hundred eighty-seven thousand, four hundred eighteen".