20120021137 has 2 divisors, whose sum is σ = 20120021138. Its totient is φ = 20120021136.

The previous prime is 20120021107. The next prime is 20120021161. The reversal of 20120021137 is 73112002102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18322600321 + 1797420816 = 135361^2 + 42396^2 .

It is a cyclic number.

It is not a de Polignac number, because 20120021137 - 2¹¹ = 20120019089 is a prime.

It is not a weakly prime, because it can be changed into another prime (20120021107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060010568 + 10060010569.

It is an arithmetic number, because the mean of its divisors is an integer number (10060010569).

Almost surely, 2^20120021137 is an apocalyptic number.

It is an amenable number.

20120021137 is a deficient number, since it is larger than the sum of its proper divisors (1).

20120021137 is an equidigital number, since it uses as much as digits as its factorization.

20120021137 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 168, while the sum is 19.

Adding to 20120021137 its reverse (73112002102), we get a palindrome (93232023239).

The spelling of 20120021137 in words is "twenty billion, one hundred twenty million, twenty-one thousand, one hundred thirty-seven".