129777649 has 2 divisors, whose sum is σ = 129777650. Its totient is φ = 129777648.

The previous prime is 129777629. The next prime is 129777667. The reversal of 129777649 is 946777921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 125283249 + 4494400 = 11193^2 + 2120^2 .

It is a cyclic number.

It is not a de Polignac number, because 129777649 - 2²⁵ = 96223217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 129777596 and 129777605.

It is not a weakly prime, because it can be changed into another prime (129777629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64888824 + 64888825.

It is an arithmetic number, because the mean of its divisors is an integer number (64888825).

Almost surely, 2^129777649 is an apocalyptic number.

It is an amenable number.

129777649 is a deficient number, since it is larger than the sum of its proper divisors (1).

129777649 is an equidigital number, since it uses as much as digits as its factorization.

129777649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1333584, while the sum is 52.

The square root of 129777649 is about 11391.9993416432. Note that the first 3 decimals coincide. The cubic root of 129777649 is about 506.2907204150.

The spelling of 129777649 in words is "one hundred twenty-nine million, seven hundred seventy-seven thousand, six hundred forty-nine".