129264840 has 48 divisors (see below), whose sum is σ = 420111900. Its totient is φ = 34470528.

The previous prime is 129264833. The next prime is 129264869. The reversal of 129264840 is 48462921.

129264840 is a `hidden beast` number, since 1 + 2 + 9 + 2 + 648 + 4 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 106626276 + 22638564 = 10326^2 + 4758^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 129264795 and 129264804.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 179175 + ... + 179894.

Almost surely, 2^129264840 is an apocalyptic number.

129264840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129264840 is an abundant number, since it is smaller than the sum of its proper divisors (290847060).

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

129264840 is a wasteful number, since it uses less digits than its factorization.

129264840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 359086 (or 359079 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 129264840 is about 11369.4696446228. The cubic root of 129264840 is about 505.6229804655.

It can be divided in two parts, 12926 and 4840, that added together give a triangular number (17766 = T₁₈₈).

The spelling of 129264840 in words is "one hundred twenty-nine million, two hundred sixty-four thousand, eight hundred forty".