129887640 has 96 divisors (see below), whose sum is σ = 424569600. Its totient is φ = 34437120.

The previous prime is 129887603. The next prime is 129887651. The reversal of 129887640 is 46788921.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 67816 + ... + 69704.

It is an arithmetic number, because the mean of its divisors is an integer number (4422600).

Almost surely, 2^129887640 is an apocalyptic number.

129887640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129887640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (212284800).

129887640 is an abundant number, since it is smaller than the sum of its proper divisors (294681960).

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

129887640 is a wasteful number, since it uses less digits than its factorization.

129887640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2097 (or 2090 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 129887640 is about 11396.8258739002. The cubic root of 129887640 is about 506.4337129312.

The spelling of 129887640 in words is "one hundred twenty-nine million, eight hundred eighty-seven thousand, six hundred forty".