21393026 has 8 divisors (see below), whose sum is σ = 32695164. Its totient is φ = 10494640.

The previous prime is 21393017. The next prime is 21393041. The reversal of 21393026 is 62039312.

It can be written as a sum of positive squares in 2 ways, for example, as 21390625 + 2401 = 4625^2 + 49^2 .

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

It is a super-2 number, since 2×21393026² = 915323122873352, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21392986 and 21393004.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 100805 + ... + 101016.

Almost surely, 2^21393026 is an apocalyptic number.

21393026 is a deficient number, since it is larger than the sum of its proper divisors (11302138).

21393026 is a wasteful number, since it uses less digits than its factorization.

21393026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201876.

The product of its (nonzero) digits is 1944, while the sum is 26.

The square root of 21393026 is about 4625.2595602842. The cubic root of 21393026 is about 277.6029474920.

It can be divided in two parts, 213 and 93026, that added together give a palindrome (93239).

The spelling of 21393026 in words is "twenty-one million, three hundred ninety-three thousand, twenty-six".