128617381 has 8 divisors (see below), whose sum is σ = 131128704. Its totient is φ = 126129120.

The previous prime is 128617351. The next prime is 128617387. The reversal of 128617381 is 183716821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 128617381 - 2⁹ = 128616869 is a prime.

It is a super-2 number, since 2×128617381² = 33084861390598322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 128617381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128617387) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5716 + ... + 17026.

It is an arithmetic number, because the mean of its divisors is an integer number (16391088).

Almost surely, 2^128617381 is an apocalyptic number.

It is an amenable number.

128617381 is a deficient number, since it is larger than the sum of its proper divisors (2511323).

128617381 is a wasteful number, since it uses less digits than its factorization.

128617381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11531.

The product of its digits is 16128, while the sum is 37.

The square root of 128617381 is about 11340.9603208899. The cubic root of 128617381 is about 504.7773825178. Note that the first 3 decimals are identical.

The spelling of 128617381 in words is "one hundred twenty-eight million, six hundred seventeen thousand, three hundred eighty-one".