72128535 has 32 divisors (see below), whose sum is σ = 124224192. Its totient is φ = 35604480.

The previous prime is 72128533. The next prime is 72128557. The reversal of 72128535 is 53582127.

It is not a de Polignac number, because 72128535 - 2¹ = 72128533 is a prime.

It is a super-2 number, since 2×72128535² = 10405051122492450, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 72128496 and 72128505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72128533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13237 + ... + 17873.

It is an arithmetic number, because the mean of its divisors is an integer number (3882006).

Almost surely, 2^72128535 is an apocalyptic number.

72128535 is a deficient number, since it is larger than the sum of its proper divisors (52095657).

72128535 is a wasteful number, since it uses less digits than its factorization.

72128535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4723.

The product of its digits is 16800, while the sum is 33.

The square root of 72128535 is about 8492.8519944716. The cubic root of 72128535 is about 416.2641763066.

The spelling of 72128535 in words is "seventy-two million, one hundred twenty-eight thousand, five hundred thirty-five".