20642270137 has 2 divisors, whose sum is σ = 20642270138. Its totient is φ = 20642270136.

The previous prime is 20642270113. The next prime is 20642270153. The reversal of 20642270137 is 73107224602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13039127721 + 7603142416 = 114189^2 + 87196^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20642270137 is a prime.

It is a super-2 number, since 2×20642270137² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20642270177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10321135068 + 10321135069.

It is an arithmetic number, because the mean of its divisors is an integer number (10321135069).

Almost surely, 2^20642270137 is an apocalyptic number.

It is an amenable number.

20642270137 is a deficient number, since it is larger than the sum of its proper divisors (1).

20642270137 is an equidigital number, since it uses as much as digits as its factorization.

20642270137 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28224, while the sum is 34.

Adding to 20642270137 its reverse (73107224602), we get a palindrome (93749494739).

The spelling of 20642270137 in words is "twenty billion, six hundred forty-two million, two hundred seventy thousand, one hundred thirty-seven".