20213985 has 16 divisors (see below), whose sum is σ = 35282880. Its totient is φ = 9800640.

The previous prime is 20213983. The next prime is 20214001. The reversal of 20213985 is 58931202.

It is a happy number.

It is not a de Polignac number, because 20213985 - 2¹ = 20213983 is a prime.

It is a super-3 number, since 3×20213985³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (20213981) 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 15 ways as a sum of consecutive naturals, for example, 61090 + ... + 61419.

It is an arithmetic number, because the mean of its divisors is an integer number (2205180).

Almost surely, 2^20213985 is an apocalyptic number.

It is an amenable number.

20213985 is a deficient number, since it is larger than the sum of its proper divisors (15068895).

20213985 is a wasteful number, since it uses less digits than its factorization.

20213985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122528.

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 20213985 is about 4495.9965524898. The cubic root of 20213985 is about 272.4064039024.

It can be divided in two parts, 2021 and 3985, that added together give a palindrome (6006).

The spelling of 20213985 in words is "twenty million, two hundred thirteen thousand, nine hundred eighty-five".