20455117 has 4 divisors (see below), whose sum is σ = 21007996. Its totient is φ = 19902240.

The previous prime is 20455109. The next prime is 20455129. The reversal of 20455117 is 71155402.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16695396 + 3759721 = 4086^2 + 1939^2 .

It is a cyclic number.

It is not a de Polignac number, because 20455117 - 2³ = 20455109 is a prime.

It is a super-2 number, since 2×20455117² = 836823622967378, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20455091 and 20455100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20455157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 276384 + ... + 276457.

It is an arithmetic number, because the mean of its divisors is an integer number (5251999).

Almost surely, 2^20455117 is an apocalyptic number.

It is an amenable number.

20455117 is a deficient number, since it is larger than the sum of its proper divisors (552879).

20455117 is an equidigital number, since it uses as much as digits as its factorization.

20455117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 552878.

The product of its (nonzero) digits is 1400, while the sum is 25.

The square root of 20455117 is about 4522.7333549525. The cubic root of 20455117 is about 273.4853010113.

The spelling of 20455117 in words is "twenty million, four hundred fifty-five thousand, one hundred seventeen".