128957940 has 96 divisors (see below), whose sum is σ = 422352000. Its totient is φ = 32576256.

The previous prime is 128957929. The next prime is 128957951. The reversal of 128957940 is 49759821.

It is an interprime number because it is at equal distance from previous prime (128957929) and next prime (128957951).

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

It is a zygodrome in base 11.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3976 + ... + 16544.

It is an arithmetic number, because the mean of its divisors is an integer number (4399500).

Almost surely, 2^128957940 is an apocalyptic number.

128957940 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 128957940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (211176000).

128957940 is an abundant number, since it is smaller than the sum of its proper divisors (293394060).

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

128957940 is a wasteful number, since it uses less digits than its factorization.

128957940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12606 (or 12598 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 45.

The square root of 128957940 is about 11355.9649523940. The cubic root of 128957940 is about 505.2225141032. Note that the first 3 decimals are identical.

The spelling of 128957940 in words is "one hundred twenty-eight million, nine hundred fifty-seven thousand, nine hundred forty".