129137538561 has 8 divisors (see below), whose sum is σ = 172492513344. Its totient is φ = 85937128080.

The previous prime is 129137538511. The next prime is 129137538571. The reversal of 129137538561 is 165835731921.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 129137538561 - 2¹⁰ = 129137537537 is a prime.

It is not an unprimeable number, because it can be changed into a prime (129137538511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38639125 + ... + 38642466.

It is an arithmetic number, because the mean of its divisors is an integer number (21561564168).

Almost surely, 2^129137538561 is an apocalyptic number.

It is an amenable number.

129137538561 is a deficient number, since it is larger than the sum of its proper divisors (43354974783).

129137538561 is an equidigital number, since it uses as much as digits as its factorization.

129137538561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77282151.

The product of its digits is 1360800, while the sum is 51.

The spelling of 129137538561 in words is "one hundred twenty-nine billion, one hundred thirty-seven million, five hundred thirty-eight thousand, five hundred sixty-one".