20505455 has 8 divisors (see below), whose sum is σ = 25010304. Its totient is φ = 16135200.

The previous prime is 20505449. The next prime is 20505467. The reversal of 20505455 is 55450502.

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

It is not a de Polignac number, because 20505455 - 2¹⁶ = 20439919 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33311 + ... + 33920.

It is an arithmetic number, because the mean of its divisors is an integer number (3126288).

Almost surely, 2^20505455 is an apocalyptic number.

20505455 is a deficient number, since it is larger than the sum of its proper divisors (4504849).

20505455 is an equidigital number, since it uses as much as digits as its factorization.

20505455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67297.

The product of its (nonzero) digits is 5000, while the sum is 26.

The square root of 20505455 is about 4528.2949329742. The cubic root of 20505455 is about 273.7094572403.

Adding to 20505455 its reverse (55450502), we get a palindrome (75955957).

The spelling of 20505455 in words is "twenty million, five hundred five thousand, four hundred fifty-five".