21812798 has 16 divisors (see below), whose sum is σ = 39361920. Its totient is φ = 8856216.

The previous prime is 21812789. The next prime is 21812821. The reversal of 21812798 is 89721812.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40736 + ... + 41267.

It is an arithmetic number, because the mean of its divisors is an integer number (2460120).

Almost surely, 2^21812798 is an apocalyptic number.

21812798 is a deficient number, since it is larger than the sum of its proper divisors (17549122).

21812798 is a wasteful number, since it uses less digits than its factorization.

21812798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82031.

The product of its digits is 16128, while the sum is 38.

The square root of 21812798 is about 4670.4173261070. The cubic root of 21812798 is about 279.4068993332.

The spelling of 21812798 in words is "twenty-one million, eight hundred twelve thousand, seven hundred ninety-eight".