20984755 has 8 divisors (see below), whose sum is σ = 27471024. Its totient is φ = 15261600.

The previous prime is 20984753. The next prime is 20984771. The reversal of 20984755 is 55748902.

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

It is not a de Polignac number, because 20984755 - 2¹ = 20984753 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20984753) 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 in 7 ways as a sum of consecutive naturals, for example, 190716 + ... + 190825.

It is an arithmetic number, because the mean of its divisors is an integer number (3433878).

Almost surely, 2^20984755 is an apocalyptic number.

20984755 is a deficient number, since it is larger than the sum of its proper divisors (6486269).

20984755 is a wasteful number, since it uses less digits than its factorization.

20984755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381557.

The product of its (nonzero) digits is 100800, while the sum is 40.

The square root of 20984755 is about 4580.9120270968. The cubic root of 20984755 is about 275.8256398905.

It can be divided in two parts, 209847 and 55, that added together give a palindrome (209902).

The spelling of 20984755 in words is "twenty million, nine hundred eighty-four thousand, seven hundred fifty-five".