129087978 has 16 divisors (see below), whose sum is σ = 264180576. Its totient is φ = 42028560.

The previous prime is 129087971. The next prime is 129087979. The reversal of 129087978 is 879780921.

It is a self number, because there is not a number n which added to its sum of digits gives 129087978.

It is not an unprimeable number, because it can be changed into a prime (129087971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 249913 + ... + 250428.

It is an arithmetic number, because the mean of its divisors is an integer number (16511286).

Almost surely, 2^129087978 is an apocalyptic number.

129087978 is an abundant number, since it is smaller than the sum of its proper divisors (135092598).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

129087978 is a wasteful number, since it uses less digits than its factorization.

129087978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500389.

The product of its (nonzero) digits is 508032, while the sum is 51.

The square root of 129087978 is about 11361.6890469683. The cubic root of 129087978 is about 505.3922750213.

The spelling of 129087978 in words is "one hundred twenty-nine million, eighty-seven thousand, nine hundred seventy-eight".