128138454612 has 144 divisors (see below), whose sum is σ = 384104680960. Its totient is φ = 35254020096.

The previous prime is 128138454547. The next prime is 128138454637. The reversal of 128138454612 is 216454831821.

128138454612 is a `hidden beast` number, since 1 + 2 + 8 + 13 + 84 + 546 + 12 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 833589 + ... + 975267.

Almost surely, 2^128138454612 is an apocalyptic number.

128138454612 is a gapful number since it is divisible by the number (12) 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 128138454612, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (192052340480).

128138454612 is an abundant number, since it is smaller than the sum of its proper divisors (255966226348).

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

128138454612 is a wasteful number, since it uses less digits than its factorization.

128138454612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141830 (or 141825 counting only the distinct ones).

The product of its digits is 368640, while the sum is 45.

The spelling of 128138454612 in words is "one hundred twenty-eight billion, one hundred thirty-eight million, four hundred fifty-four thousand, six hundred twelve".