128961869040 has 480 divisors, whose sum is σ = 472635124416. Its totient is φ = 32636805120.

The previous prime is 128961869039. The next prime is 128961869111. The reversal of 128961869040 is 40968169821.

128961869040 is a `hidden beast` number, since 12 + 8 + 9 + 618 + 6 + 9 + 0 + 4 + 0 = 666.

It is a super-2 number, since 2×128961869040² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 29488294 + ... + 29492666.

Almost surely, 2^128961869040 is an apocalyptic number.

128961869040 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 128961869040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (236317562208).

128961869040 is an abundant number, since it is smaller than the sum of its proper divisors (343673255376).

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

128961869040 is a wasteful number, since it uses less digits than its factorization.

128961869040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4479 (or 4461 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 54.

It can be divided in two parts, 128961 and 869040, that added together give a square (998001 = 999²).

The spelling of 128961869040 in words is "one hundred twenty-eight billion, nine hundred sixty-one million, eight hundred sixty-nine thousand, forty".