20507213737 has 4 divisors (see below), whose sum is σ = 20560757760. Its totient is φ = 20453669716.

The previous prime is 20507213731. The next prime is 20507213773. The reversal of 20507213737 is 73731270502.

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 a de Polignac number, because none of the positive numbers 2^k-20507213737 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20507213696 and 20507213705.

It is not an unprimeable number, because it can be changed into a prime (20507213731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26771437 + ... + 26772202.

It is an arithmetic number, because the mean of its divisors is an integer number (5140189440).

Almost surely, 2^20507213737 is an apocalyptic number.

It is an amenable number.

20507213737 is a deficient number, since it is larger than the sum of its proper divisors (53544023).

20507213737 is an equidigital number, since it uses as much as digits as its factorization.

20507213737 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53544022.

The product of its (nonzero) digits is 61740, while the sum is 37.

The spelling of 20507213737 in words is "twenty billion, five hundred seven million, two hundred thirteen thousand, seven hundred thirty-seven".