20117658 has 16 divisors (see below), whose sum is σ = 43893216. Its totient is φ = 6096240.

The previous prime is 20117627. The next prime is 20117693. The reversal of 20117658 is 85671102.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 152341 + ... + 152472.

It is an arithmetic number, because the mean of its divisors is an integer number (2743326).

Almost surely, 2^20117658 is an apocalyptic number.

20117658 is an abundant number, since it is smaller than the sum of its proper divisors (23775558).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20117658 is a wasteful number, since it uses less digits than its factorization.

20117658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304829.

The product of its (nonzero) digits is 3360, while the sum is 30.

The square root of 20117658 is about 4485.2712292569. The cubic root of 20117658 is about 271.9730095046.

It can be divided in two parts, 2011 and 7658, that added together give a palindrome (9669).

The spelling of 20117658 in words is "twenty million, one hundred seventeen thousand, six hundred fifty-eight".