21040313 has 8 divisors (see below), whose sum is σ = 24088128. Its totient is φ = 18003024.

The previous prime is 21040297. The next prime is 21040387. The reversal of 21040313 is 31304012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21040313 - 2⁴ = 21040297 is a prime.

It is a super-2 number, since 2×21040313² = 885389542275938, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21040213) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2270 + ... + 6872.

It is an arithmetic number, because the mean of its divisors is an integer number (3011016).

Almost surely, 2^21040313 is an apocalyptic number.

It is an amenable number.

21040313 is a deficient number, since it is larger than the sum of its proper divisors (3047815).

21040313 is an equidigital number, since it uses as much as digits as its factorization.

21040313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5263.

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 21040313 is about 4586.9720949664. The cubic root of 21040313 is about 276.0688452847.

Adding to 21040313 its reverse (31304012), we get a palindrome (52344325).

The spelling of 21040313 in words is "twenty-one million, forty thousand, three hundred thirteen".