20042137 has 4 divisors (see below), whose sum is σ = 20240676. Its totient is φ = 19843600.

The previous prime is 20042117. The next prime is 20042173. The reversal of 20042137 is 73124002.

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

It can be written as a sum of positive squares in 2 ways, for example, as 14561856 + 5480281 = 3816^2 + 2341^2 .

It is a cyclic number.

It is not a de Polignac number, because 20042137 - 2²³ = 11653529 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, 99118 + ... + 99319.

It is an arithmetic number, because the mean of its divisors is an integer number (5060169).

Almost surely, 2^20042137 is an apocalyptic number.

It is an amenable number.

20042137 is a deficient number, since it is larger than the sum of its proper divisors (198539).

20042137 is a wasteful number, since it uses less digits than its factorization.

20042137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198538.

The product of its (nonzero) digits is 336, while the sum is 19.

The square root of 20042137 is about 4476.8445360544. The cubic root of 20042137 is about 271.6322569656.

Adding to 20042137 its reverse (73124002), we get a palindrome (93166139).

The spelling of 20042137 in words is "twenty million, forty-two thousand, one hundred thirty-seven".