20042147 has 4 divisors (see below), whose sum is σ = 20074056. Its totient is φ = 20010240.

The previous prime is 20042117. The next prime is 20042173. The reversal of 20042147 is 74124002.

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

It is a cyclic number.

It is not a de Polignac number, because 20042147 - 2⁸ = 20041891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20042107) 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, 14993 + ... + 16274.

It is an arithmetic number, because the mean of its divisors is an integer number (5018514).

Almost surely, 2^20042147 is an apocalyptic number.

20042147 is a deficient number, since it is larger than the sum of its proper divisors (31909).

20042147 is an equidigital number, since it uses as much as digits as its factorization.

20042147 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31908.

The product of its (nonzero) digits is 448, while the sum is 20.

The square root of 20042147 is about 4476.8456529123. The cubic root of 20042147 is about 271.6323021424.

Adding to 20042147 its reverse (74124002), we get a palindrome (94166149).

The spelling of 20042147 in words is "twenty million, forty-two thousand, one hundred forty-seven".