21812126 has 8 divisors (see below), whose sum is σ = 37392240. Its totient is φ = 9348048.

The previous prime is 21812113. The next prime is 21812143. The reversal of 21812126 is 62121812.

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

It is a congruent number.

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, 778991 + ... + 779018.

It is an arithmetic number, because the mean of its divisors is an integer number (4674030).

Almost surely, 2^21812126 is an apocalyptic number.

21812126 is a deficient number, since it is larger than the sum of its proper divisors (15580114).

21812126 is a wasteful number, since it uses less digits than its factorization.

21812126 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1558018.

The product of its digits is 384, while the sum is 23.

The square root of 21812126 is about 4670.3453833737. The cubic root of 21812126 is about 279.4040300183.

Adding to 21812126 its reverse (62121812), we get a palindrome (83933938).

The spelling of 21812126 in words is "twenty-one million, eight hundred twelve thousand, one hundred twenty-six".