21818256946 has 16 divisors (see below), whose sum is σ = 33057782208. Its totient is φ = 10799038000.

The previous prime is 21818256919. The next prime is 21818256979. The reversal of 21818256946 is 64965281812.

It is a junction number, because it is equal to n+sod(n) for n = 21818256893 and 21818256902.

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, 2035461 + ... + 2046151.

It is an arithmetic number, because the mean of its divisors is an integer number (2066111388).

Almost surely, 2^21818256946 is an apocalyptic number.

21818256946 is a deficient number, since it is larger than the sum of its proper divisors (11239525262).

21818256946 is a wasteful number, since it uses less digits than its factorization.

21818256946 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20897.

The product of its digits is 1658880, while the sum is 52.

The spelling of 21818256946 in words is "twenty-one billion, eight hundred eighteen million, two hundred fifty-six thousand, nine hundred forty-six".