10140021 has 6 divisors (see below), whose sum is σ = 14646710. Its totient is φ = 6760008.

The previous prime is 10140019. The next prime is 10140029. The reversal of 10140021 is 12004101.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 7535025 + 2604996 = 2745^2 + 1614^2 .

It is not a de Polignac number, because 10140021 - 2¹ = 10140019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 1126669 = 10140021 / (1 + 0 + 1 + 4 + 0 + 0 + 2 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10139985 and 10140012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10140029) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 563326 + ... + 563343.

Almost surely, 2^10140021 is an apocalyptic number.

It is an amenable number.

10140021 is a deficient number, since it is larger than the sum of its proper divisors (4506689).

10140021 is a wasteful number, since it uses less digits than its factorization.

10140021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1126675 (or 1126672 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 10140021 is about 3184.3399630065. The cubic root of 10140021 is about 216.4443655528. Note that the first 3 decimals are identical.

Adding to 10140021 its reverse (12004101), we get a palindrome (22144122).

The spelling of 10140021 in words is "ten million, one hundred forty thousand, twenty-one".