20681042 has 8 divisors (see below), whose sum is σ = 31111500. Its totient is φ = 10310544.

The previous prime is 20681041. The next prime is 20681069. The reversal of 20681042 is 24018602.

It can be written as a sum of positive squares in 2 ways, for example, as 18156121 + 2524921 = 4261^2 + 1589^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 20680999 and 20681017.

It is not an unprimeable number, because it can be changed into a prime (20681041) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14117 + ... + 15512.

Almost surely, 2^20681042 is an apocalyptic number.

20681042 is a deficient number, since it is larger than the sum of its proper divisors (10430458).

20681042 is a wasteful number, since it uses less digits than its factorization.

20681042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29980.

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 20681042 is about 4547.6413666867. The cubic root of 20681042 is about 274.4884904868.

Adding to 20681042 its reverse (24018602), we get a palindrome (44699644).

The spelling of 20681042 in words is "twenty million, six hundred eighty-one thousand, forty-two".