20121090137 has 2 divisors, whose sum is σ = 20121090138. Its totient is φ = 20121090136.

The previous prime is 20121090091. The next prime is 20121090149. The reversal of 20121090137 is 73109012102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19657161616 + 463928521 = 140204^2 + 21539^2 .

It is a cyclic number.

It is not a de Polignac number, because 20121090137 - 2⁸ = 20121089881 is a prime.

It is not a weakly prime, because it can be changed into another prime (20121090037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060545068 + 10060545069.

It is an arithmetic number, because the mean of its divisors is an integer number (10060545069).

Almost surely, 2^20121090137 is an apocalyptic number.

It is an amenable number.

20121090137 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121090137 is an equidigital number, since it uses as much as digits as its factorization.

20121090137 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 756, while the sum is 26.

The spelling of 20121090137 in words is "twenty billion, one hundred twenty-one million, ninety thousand, one hundred thirty-seven".