140440021 has 4 divisors (see below), whose sum is σ = 143706112. Its totient is φ = 137173932.

The previous prime is 140440019. The next prime is 140440037. The reversal of 140440021 is 120044041.

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 140440021 - 2¹ = 140440019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 140439977 and 140440004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (140440081) 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, 1632981 + ... + 1633066.

It is an arithmetic number, because the mean of its divisors is an integer number (35926528).

Almost surely, 2^140440021 is an apocalyptic number.

It is an amenable number.

140440021 is a deficient number, since it is larger than the sum of its proper divisors (3266091).

140440021 is an equidigital number, since it uses as much as digits as its factorization.

140440021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3266090.

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 140440021 is about 11850.7392596411. The cubic root of 140440021 is about 519.7928427797.

Adding to 140440021 its reverse (120044041), we get a palindrome (260484062).

The spelling of 140440021 in words is "one hundred forty million, four hundred forty thousand, twenty-one".