128151531 has 16 divisors (see below), whose sum is σ = 190050720. Its totient is φ = 85345920.

The previous prime is 128151511. The next prime is 128151533. The reversal of 128151531 is 135151821.

128151531 is a `hidden beast` number, since 1 + 2 + 81 + 51 + 531 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-128151531 is a prime.

It is a super-2 number, since 2×128151531² = 32845629795287922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 128151495 and 128151504.

It is not an unprimeable number, because it can be changed into a prime (128151533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33871 + ... + 37463.

It is an arithmetic number, because the mean of its divisors is an integer number (11878170).

Almost surely, 2^128151531 is an apocalyptic number.

128151531 is a deficient number, since it is larger than the sum of its proper divisors (61899189).

128151531 is a wasteful number, since it uses less digits than its factorization.

128151531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4923 (or 4917 counting only the distinct ones).

The product of its digits is 1200, while the sum is 27.

The square root of 128151531 is about 11320.4033055364. The cubic root of 128151531 is about 504.1672135079.

The spelling of 128151531 in words is "one hundred twenty-eight million, one hundred fifty-one thousand, five hundred thirty-one".