21423113 has 4 divisors (see below), whose sum is σ = 21432528. Its totient is φ = 21413700.

The previous prime is 21423107. The next prime is 21423119. The reversal of 21423113 is 31132412.

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 a brilliant number, because the two primes have the same length.

It is an interprime number because it is at equal distance from previous prime (21423107) and next prime (21423119).

It is a cyclic number.

It is not a de Polignac number, because 21423113 - 2¹⁴ = 21406729 is a prime.

It is a super-2 number, since 2×21423113² = 917899541221538, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21423091 and 21423100.

It is not an unprimeable number, because it can be changed into a prime (21423119) 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, 1070 + ... + 6632.

It is an arithmetic number, because the mean of its divisors is an integer number (5358132).

Almost surely, 2^21423113 is an apocalyptic number.

It is an amenable number.

21423113 is a deficient number, since it is larger than the sum of its proper divisors (9415).

21423113 is an equidigital number, since it uses as much as digits as its factorization.

21423113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9414.

The product of its digits is 144, while the sum is 17.

The square root of 21423113 is about 4628.5108836428. The cubic root of 21423113 is about 277.7330261358.

Adding to 21423113 its reverse (31132412), we get a palindrome (52555525).

The spelling of 21423113 in words is "twenty-one million, four hundred twenty-three thousand, one hundred thirteen".