129291990 has 16 divisors (see below), whose sum is σ = 310300848. Its totient is φ = 34477856.

The previous prime is 129291961. The next prime is 129291997. The reversal of 129291990 is 99192921.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129291997) 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, 2154837 + ... + 2154896.

It is an arithmetic number, because the mean of its divisors is an integer number (19393803).

Almost surely, 2^129291990 is an apocalyptic number.

129291990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

129291990 is an abundant number, since it is smaller than the sum of its proper divisors (181008858).

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

129291990 is a wasteful number, since it uses less digits than its factorization.

129291990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4309743.

The product of its (nonzero) digits is 26244, while the sum is 42.

The square root of 129291990 is about 11370.6635690271. The cubic root of 129291990 is about 505.6583773116.

The spelling of 129291990 in words is "one hundred twenty-nine million, two hundred ninety-one thousand, nine hundred ninety".