21313418 has 8 divisors (see below), whose sum is σ = 36537312. Its totient is φ = 9134316.

The previous prime is 21313379. The next prime is 21313429. The reversal of 21313418 is 81431312.

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

It is a junction number, because it is equal to n+sod(n) for n = 21313393 and 21313402.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 761180 + ... + 761207.

It is an arithmetic number, because the mean of its divisors is an integer number (4567164).

Almost surely, 2^21313418 is an apocalyptic number.

21313418 is a deficient number, since it is larger than the sum of its proper divisors (15223894).

21313418 is a wasteful number, since it uses less digits than its factorization.

21313418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1522396.

The product of its digits is 576, while the sum is 23.

The square root of 21313418 is about 4616.6457520585. The cubic root of 21313418 is about 277.2581796151.

It can be divided in two parts, 213 and 13418, that added together give a palindrome (13631).

The spelling of 21313418 in words is "twenty-one million, three hundred thirteen thousand, four hundred eighteen".