87129140 has 24 divisors (see below), whose sum is σ = 209110272. Its totient is φ = 29872800.

The previous prime is 87129121. The next prime is 87129149. The reversal of 87129140 is 4192178.

87129140 is digitally balanced in base 9, because in such base it contains all the possibile digits an equal number of times.

87129140 is strictly pandigital in base 9.

It is a junction number, because it is equal to n+sod(n) for n = 87129097 and 87129106.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87129149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 311036 + ... + 311315.

It is an arithmetic number, because the mean of its divisors is an integer number (8712928).

Almost surely, 2^87129140 is an apocalyptic number.

It is an amenable number.

87129140 is an abundant number, since it is smaller than the sum of its proper divisors (121981132).

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

87129140 is a wasteful number, since it uses less digits than its factorization.

87129140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 622367 (or 622365 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 32.

The square root of 87129140 is about 9334.2991166986. The cubic root of 87129140 is about 443.3238972621.

The spelling of 87129140 in words is "eighty-seven million, one hundred twenty-nine thousand, one hundred forty".