21400313 has 4 divisors (see below), whose sum is σ = 23345808. Its totient is φ = 19454820.

The previous prime is 21400277. The next prime is 21400343. The reversal of 21400313 is 31300412.

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 not a de Polignac number, because 21400313 - 2²⁴ = 4623097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21400343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 972731 + ... + 972752.

It is an arithmetic number, because the mean of its divisors is an integer number (5836452).

Almost surely, 2^21400313 is an apocalyptic number.

It is an amenable number.

21400313 is a deficient number, since it is larger than the sum of its proper divisors (1945495).

21400313 is a wasteful number, since it uses less digits than its factorization.

21400313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1945494.

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

The square root of 21400313 is about 4626.0472327896. The cubic root of 21400313 is about 277.6344634175.

Adding to 21400313 its reverse (31300412), we get a palindrome (52700725).

Subtracting 21400313 from its reverse (31300412), we obtain a palindrome (9900099).

The spelling of 21400313 in words is "twenty-one million, four hundred thousand, three hundred thirteen".