140520257 has 4 divisors (see below), whose sum is σ = 147916080. Its totient is φ = 133124436.

The previous prime is 140520251. The next prime is 140520277. The reversal of 140520257 is 752025041.

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 140520257 - 2¹² = 140516161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (140520251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3697883 + ... + 3697920.

It is an arithmetic number, because the mean of its divisors is an integer number (36979020).

Almost surely, 2^140520257 is an apocalyptic number.

It is an amenable number.

140520257 is a deficient number, since it is larger than the sum of its proper divisors (7395823).

140520257 is an equidigital number, since it uses as much as digits as its factorization.

140520257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7395822.

The product of its (nonzero) digits is 2800, while the sum is 26.

The square root of 140520257 is about 11854.1240503042. The cubic root of 140520257 is about 519.8918130453.

Adding to 140520257 its reverse (752025041), we get a palindrome (892545298).

The spelling of 140520257 in words is "one hundred forty million, five hundred twenty thousand, two hundred fifty-seven".