20906518 has 8 divisors (see below), whose sum is σ = 31801680. Its totient is φ = 10305960.

The previous prime is 20906503. The next prime is 20906521. The reversal of 20906518 is 81560902.

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

It is a self number, because there is not a number n which added to its sum of digits gives 20906518.

It is a congruent number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 73473 + ... + 73756.

It is an arithmetic number, because the mean of its divisors is an integer number (3975210).

Almost surely, 2^20906518 is an apocalyptic number.

20906518 is a deficient number, since it is larger than the sum of its proper divisors (10895162).

20906518 is a wasteful number, since it uses less digits than its factorization.

20906518 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147302.

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 20906518 is about 4572.3645961362. The cubic root of 20906518 is about 275.4824281203.

The spelling of 20906518 in words is "twenty million, nine hundred six thousand, five hundred eighteen".