140021021 has 4 divisors (see below), whose sum is σ = 160024032. Its totient is φ = 120018012.

The previous prime is 140021003. The next prime is 140021023. The reversal of 140021021 is 120120041.

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: 120120041 = 61 ⋅1969181.

It is a cyclic number.

It is not a de Polignac number, because 140021021 - 2⁶ = 140020957 is a prime.

140021021 is a modest number, since divided by 21021 gives 140 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 140020993 and 140021011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (140021023) 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, 10001495 + ... + 10001508.

It is an arithmetic number, because the mean of its divisors is an integer number (40006008).

Almost surely, 2^140021021 is an apocalyptic number.

It is an amenable number.

140021021 is a deficient number, since it is larger than the sum of its proper divisors (20003011).

140021021 is an equidigital number, since it uses as much as digits as its factorization.

140021021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20003010.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 140021021 is about 11833.0478322366. The cubic root of 140021021 is about 519.2753973175.

Adding to 140021021 its reverse (120120041), we get a palindrome (260141062).

The spelling of 140021021 in words is "one hundred forty million, twenty-one thousand, twenty-one".