129787745 has 4 divisors (see below), whose sum is σ = 155745300. Its totient is φ = 103830192.

The previous prime is 129787739. The next prime is 129787751. The reversal of 129787745 is 547787921.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (129787739) and next prime (129787751).

It can be written as a sum of positive squares in 2 ways, for example, as 20647936 + 109139809 = 4544^2 + 10447^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129787745 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 129787693 and 129787702.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12978770 + ... + 12978779.

It is an arithmetic number, because the mean of its divisors is an integer number (38936325).

Almost surely, 2^129787745 is an apocalyptic number.

It is an amenable number.

129787745 is a deficient number, since it is larger than the sum of its proper divisors (25957555).

129787745 is an equidigital number, since it uses as much as digits as its factorization.

129787745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25957554.

The product of its digits is 987840, while the sum is 50.

The square root of 129787745 is about 11392.4424510287. The cubic root of 129787745 is about 506.3038489689.

The spelling of 129787745 in words is "one hundred twenty-nine million, seven hundred eighty-seven thousand, seven hundred forty-five".