140135821 has 4 divisors (see below), whose sum is σ = 160155232. Its totient is φ = 120116412.

The previous prime is 140135813. The next prime is 140135857. The reversal of 140135821 is 128531041.

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.

It is a cyclic number.

It is not a de Polignac number, because 140135821 - 2³ = 140135813 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 (140135881) 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, 10009695 + ... + 10009708.

It is an arithmetic number, because the mean of its divisors is an integer number (40038808).

Almost surely, 2^140135821 is an apocalyptic number.

It is an amenable number.

140135821 is a deficient number, since it is larger than the sum of its proper divisors (20019411).

140135821 is an equidigital number, since it uses as much as digits as its factorization.

140135821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20019410.

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 140135821 is about 11837.8976596353. The cubic root of 140135821 is about 519.4172725180.

Adding to 140135821 its reverse (128531041), we get a palindrome (268666862).

The spelling of 140135821 in words is "one hundred forty million, one hundred thirty-five thousand, eight hundred twenty-one".