21548313 has 6 divisors (see below), whose sum is σ = 31125354. Its totient is φ = 14365536.

The previous prime is 21548291. The next prime is 21548323. The reversal of 21548313 is 31384512.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 14953689 + 6594624 = 3867^2 + 2568^2 .

It is not a de Polignac number, because 21548313 - 2⁵ = 21548281 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21548323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1197120 + ... + 1197137.

It is an arithmetic number, because the mean of its divisors is an integer number (5187559).

Almost surely, 2^21548313 is an apocalyptic number.

It is an amenable number.

21548313 is a deficient number, since it is larger than the sum of its proper divisors (9577041).

21548313 is a wasteful number, since it uses less digits than its factorization.

21548313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2394263 (or 2394260 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 21548313 is about 4642.0160490890. The cubic root of 21548313 is about 278.2730138888.

It can be divided in two parts, 215483 and 13, that added together give a triangular number (215496 = T₆₅₆).

The spelling of 21548313 in words is "twenty-one million, five hundred forty-eight thousand, three hundred thirteen".