20042537 has 4 divisors (see below), whose sum is σ = 20296320. Its totient is φ = 19788756.

The previous prime is 20042527. The next prime is 20042551. The reversal of 20042537 is 73524002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20042537 - 2⁴ = 20042521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20042527) 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, 126773 + ... + 126930.

It is an arithmetic number, because the mean of its divisors is an integer number (5074080).

Almost surely, 2^20042537 is an apocalyptic number.

It is an amenable number.

20042537 is a deficient number, since it is larger than the sum of its proper divisors (253783).

20042537 is an equidigital number, since it uses as much as digits as its factorization.

20042537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253782.

The product of its (nonzero) digits is 1680, while the sum is 23.

The square root of 20042537 is about 4476.8892101547. The cubic root of 20042537 is about 271.6340640280.

Adding to 20042537 its reverse (73524002), we get a palindrome (93566539).

The spelling of 20042537 in words is "twenty million, forty-two thousand, five hundred thirty-seven".