121312729 has 2 divisors, whose sum is σ = 121312730. Its totient is φ = 121312728.

The previous prime is 121312699. The next prime is 121312733. The reversal of 121312729 is 927213121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 100400400 + 20912329 = 10020^2 + 4573^2 .

It is an emirp because it is prime and its reverse (927213121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121312729 - 2²³ = 112924121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121312697 and 121312706.

It is not a weakly prime, because it can be changed into another prime (121312229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60656364 + 60656365.

It is an arithmetic number, because the mean of its divisors is an integer number (60656365).

Almost surely, 2^121312729 is an apocalyptic number.

It is an amenable number.

121312729 is a deficient number, since it is larger than the sum of its proper divisors (1).

121312729 is an equidigital number, since it uses as much as digits as its factorization.

121312729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1512, while the sum is 28.

The square root of 121312729 is about 11014.2057816258. The cubic root of 121312729 is about 495.0344893154.

The spelling of 121312729 in words is "one hundred twenty-one million, three hundred twelve thousand, seven hundred twenty-nine".