21347613178 has 8 divisors (see below), whose sum is σ = 32255153172. Its totient is φ = 10595895456.

The previous prime is 21347613107. The next prime is 21347613193. The reversal of 21347613178 is 87131674312.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 19467783729 + 1879829449 = 139527^2 + 43357^2 .

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

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, 38955225 + ... + 38955772.

Almost surely, 2^21347613178 is an apocalyptic number.

21347613178 is a deficient number, since it is larger than the sum of its proper divisors (10907539994).

21347613178 is a wasteful number, since it uses less digits than its factorization.

21347613178 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77911136.

The product of its digits is 169344, while the sum is 43.

The spelling of 21347613178 in words is "twenty-one billion, three hundred forty-seven million, six hundred thirteen thousand, one hundred seventy-eight".