21518114 has 4 divisors (see below), whose sum is σ = 32277174. Its totient is φ = 10759056.

The previous prime is 21518111. The next prime is 21518131. The reversal of 21518114 is 41181512.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 15342889 + 6175225 = 3917^2 + 2485^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21518114.

It is not an unprimeable number, because it can be changed into a prime (21518111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5379527 + ... + 5379530.

Almost surely, 2^21518114 is an apocalyptic number.

21518114 is a deficient number, since it is larger than the sum of its proper divisors (10759060).

21518114 is a wasteful number, since it uses less digits than its factorization.

21518114 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10759059.

The product of its digits is 320, while the sum is 23.

The square root of 21518114 is about 4638.7621193590. The cubic root of 21518114 is about 278.1429573727.

Adding to 21518114 its reverse (41181512), we get a palindrome (62699626).

The spelling of 21518114 in words is "twenty-one million, five hundred eighteen thousand, one hundred fourteen".