21439178248 has 32 divisors (see below), whose sum is σ = 40457293560. Its totient is φ = 10650787840.

The previous prime is 21439178231. The next prime is 21439178249. The reversal of 21439178248 is 84287193412.

It can be written as a sum of positive squares in 4 ways, for example, as 21426518884 + 12659364 = 146378^2 + 3558^2 .

It is not an unprimeable number, because it can be changed into a prime (21439178249) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 780036 + ... + 807052.

Almost surely, 2^21439178248 is an apocalyptic number.

It is an amenable number.

21439178248 is a deficient number, since it is larger than the sum of its proper divisors (19018115312).

21439178248 is a wasteful number, since it uses less digits than its factorization.

21439178248 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27657 (or 27653 counting only the distinct ones).

The product of its digits is 774144, while the sum is 49.

The spelling of 21439178248 in words is "twenty-one billion, four hundred thirty-nine million, one hundred seventy-eight thousand, two hundred forty-eight".