20520340037 has 4 divisors (see below), whose sum is σ = 20856739116. Its totient is φ = 20183940960.

The previous prime is 20520340019. The next prime is 20520340063. The reversal of 20520340037 is 73004302502.

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 619312996 + 19901027041 = 24886^2 + 141071^2 .

It is a cyclic number.

It is not a de Polignac number, because 20520340037 - 2²⁸ = 20251904581 is a prime.

It is a super-2 number, since 2×20520340037² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20520339988 and 20520340015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20520340097) 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, 168199448 + ... + 168199569.

It is an arithmetic number, because the mean of its divisors is an integer number (5214184779).

Almost surely, 2^20520340037 is an apocalyptic number.

It is an amenable number.

20520340037 is a deficient number, since it is larger than the sum of its proper divisors (336399079).

20520340037 is an equidigital number, since it uses as much as digits as its factorization.

20520340037 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 336399078.

The product of its (nonzero) digits is 5040, while the sum is 26.

Adding to 20520340037 its reverse (73004302502), we get a palindrome (93524642539).

The spelling of 20520340037 in words is "twenty billion, five hundred twenty million, three hundred forty thousand, thirty-seven".