21318154 has 32 divisors (see below), whose sum is σ = 37920960. Its totient is φ = 8860800.

The previous prime is 21318149. The next prime is 21318181. The reversal of 21318154 is 45181312.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37182 + ... + 37750.

It is an arithmetic number, because the mean of its divisors is an integer number (1185030).

Almost surely, 2^21318154 is an apocalyptic number.

21318154 is a deficient number, since it is larger than the sum of its proper divisors (16602806).

21318154 is a wasteful number, since it uses less digits than its factorization.

21318154 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 726.

The product of its digits is 960, while the sum is 25.

The square root of 21318154 is about 4617.1586500791. The cubic root of 21318154 is about 277.2787143707.

Adding to 21318154 its reverse (45181312), we get a palindrome (66499466).

The spelling of 21318154 in words is "twenty-one million, three hundred eighteen thousand, one hundred fifty-four".