129853840 has 20 divisors (see below), whose sum is σ = 301910364. Its totient is φ = 51941504.

The previous prime is 129853813. The next prime is 129853849. The reversal of 129853840 is 48358921.

It can be written as a sum of positive squares in 2 ways, for example, as 49787136 + 80066704 = 7056^2 + 8948^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 129853793 and 129853802.

It is not an unprimeable number, because it can be changed into a prime (129853849) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 811507 + ... + 811666.

Almost surely, 2^129853840 is an apocalyptic number.

129853840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129853840 is an abundant number, since it is smaller than the sum of its proper divisors (172056524).

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

129853840 is a wasteful number, since it uses less digits than its factorization.

129853840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1623186 (or 1623180 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 40.

The square root of 129853840 is about 11395.3429083990. The cubic root of 129853840 is about 506.3897802303.

The spelling of 129853840 in words is "one hundred twenty-nine million, eight hundred fifty-three thousand, eight hundred forty".