20020842 has 12 divisors (see below), whose sum is σ = 43378530. Its totient is φ = 6673608.

The previous prime is 20020841. The next prime is 20020901. The reversal of 20020842 is 24802002.

It can be written as a sum of positive squares in only one way, i.e., 17464041 + 2556801 = 4179^2 + 1599^2 .

It is a super-2 number, since 2×20020842² = 801668228777928, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18), and also a Moran number because the ratio is a prime number: 1112269 = 20020842 / (2 + 0 + 0 + 2 + 0 + 8 + 4 + 2).

It is not an unprimeable number, because it can be changed into a prime (20020841) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 556117 + ... + 556152.

Almost surely, 2^20020842 is an apocalyptic number.

20020842 is an abundant number, since it is smaller than the sum of its proper divisors (23357688).

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

20020842 is a wasteful number, since it uses less digits than its factorization.

20020842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1112277 (or 1112274 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 20020842 is about 4474.4655546780. The cubic root of 20020842 is about 271.5360187452.

Adding to 20020842 its reverse (24802002), we get a palindrome (44822844).

The spelling of 20020842 in words is "twenty million, twenty thousand, eight hundred forty-two".