129137993 has 2 divisors, whose sum is σ = 129137994. Its totient is φ = 129137992.

The previous prime is 129137989. The next prime is 129138007. The reversal of 129137993 is 399731921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 90859024 + 38278969 = 9532^2 + 6187^2 .

It is an emirp because it is prime and its reverse (399731921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 129137993 - 2² = 129137989 is a prime.

It is not a weakly prime, because it can be changed into another prime (129137093) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64568996 + 64568997.

It is an arithmetic number, because the mean of its divisors is an integer number (64568997).

Almost surely, 2^129137993 is an apocalyptic number.

It is an amenable number.

129137993 is a deficient number, since it is larger than the sum of its proper divisors (1).

129137993 is an equidigital number, since it uses as much as digits as its factorization.

129137993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 91854, while the sum is 44.

The square root of 129137993 is about 11363.8898709905. The cubic root of 129137993 is about 505.4575378268.

The spelling of 129137993 in words is "one hundred twenty-nine million, one hundred thirty-seven thousand, nine hundred ninety-three".