28138916512500 has 72 divisors (see below), whose sum is σ = 82066587339744. Its totient is φ = 7503711060000.

The previous prime is 28138916512439. The next prime is 28138916512507. The reversal of 28138916512500 is 521561983182.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28138916512507) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 375148054 + ... + 375223053.

It is an arithmetic number, because the mean of its divisors is an integer number (1139813713052).

Almost surely, 2^{28138916512500} is an apocalyptic number.

28138916512500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28138916512500 is an abundant number, since it is smaller than the sum of its proper divisors (53927670827244).

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

28138916512500 is an equidigital number, since it uses as much as digits as its factorization.

28138916512500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 750371139 (or 750371117 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 51.

The spelling of 28138916512500 in words is "twenty-eight trillion, one hundred thirty-eight billion, nine hundred sixteen million, five hundred twelve thousand, five hundred".