140528509 has 4 divisors (see below), whose sum is σ = 153303840. Its totient is φ = 127753180.

The previous prime is 140528497. The next prime is 140528533. The reversal of 140528509 is 905825041.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 905825041 = 11 ⋅82347731.

It is a cyclic number.

It is not a de Polignac number, because 140528509 - 2²⁷ = 6310781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (140528539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6387649 + ... + 6387670.

It is an arithmetic number, because the mean of its divisors is an integer number (38325960).

Almost surely, 2^140528509 is an apocalyptic number.

It is an amenable number.

140528509 is a deficient number, since it is larger than the sum of its proper divisors (12775331).

140528509 is a wasteful number, since it uses less digits than its factorization.

140528509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12775330.

The product of its (nonzero) digits is 14400, while the sum is 34.

The square root of 140528509 is about 11854.4721097145. The cubic root of 140528509 is about 519.9019896641.

The spelling of 140528509 in words is "one hundred forty million, five hundred twenty-eight thousand, five hundred nine".