20642042 has 4 divisors (see below), whose sum is σ = 30963066. Its totient is φ = 10321020.

The previous prime is 20642023. The next prime is 20642047. The reversal of 20642042 is 24024602.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 15217801 + 5424241 = 3901^2 + 2329^2 .

It is not an unprimeable number, because it can be changed into a prime (20642047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5160509 + ... + 5160512.

Almost surely, 2^20642042 is an apocalyptic number.

20642042 is a deficient number, since it is larger than the sum of its proper divisors (10321024).

20642042 is a wasteful number, since it uses less digits than its factorization.

20642042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10321023.

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 20642042 is about 4543.3514061758. The cubic root of 20642042 is about 274.3158398159.

Adding to 20642042 its reverse (24024602), we get a palindrome (44666644).

The spelling of 20642042 in words is "twenty million, six hundred forty-two thousand, forty-two".