20355988 has 12 divisors (see below), whose sum is σ = 35655732. Its totient is φ = 10168640.

The previous prime is 20355961. The next prime is 20356013. The reversal of 20355988 is 88955302.

It can be written as a sum of positive squares in 2 ways, for example, as 9253764 + 11102224 = 3042^2 + 3332^2 .

It is a super-2 number, since 2×20355988² = 828732494912288, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20355988.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 5406 + ... + 8362.

It is an arithmetic number, because the mean of its divisors is an integer number (2971311).

Almost surely, 2^20355988 is an apocalyptic number.

It is an amenable number.

20355988 is a deficient number, since it is larger than the sum of its proper divisors (15299744).

20355988 is a wasteful number, since it uses less digits than its factorization.

20355988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4682 (or 4680 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 40.

The square root of 20355988 is about 4511.7610752344. The cubic root of 20355988 is about 273.0427998929.

The spelling of 20355988 in words is "twenty million, three hundred fifty-five thousand, nine hundred eighty-eight".