21278332246 has 8 divisors (see below), whose sum is σ = 31922090064. Its totient is φ = 10637635560.

The previous prime is 21278332211. The next prime is 21278332249. The reversal of 21278332246 is 64223387212.

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

It is a junction number, because it is equal to n+sod(n) for n = 21278332199 and 21278332208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21278332249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 747825 + ... + 775756.

It is an arithmetic number, because the mean of its divisors is an integer number (3990261258).

Almost surely, 2^21278332246 is an apocalyptic number.

21278332246 is a deficient number, since it is larger than the sum of its proper divisors (10643757818).

21278332246 is a wasteful number, since it uses less digits than its factorization.

21278332246 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1530566.

The product of its digits is 193536, while the sum is 40.

The spelling of 21278332246 in words is "twenty-one billion, two hundred seventy-eight million, three hundred thirty-two thousand, two hundred forty-six".