16421878556 has 12 divisors (see below), whose sum is σ = 28740054168. Its totient is φ = 8210434512.

The previous prime is 16421878547. The next prime is 16421878573. The reversal of 16421878556 is 65587812461.

It is a hoax number, since the sum of its digits (53) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 16421878498 and 16421878507.

It is a congruent number.

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, 47546 + ... + 187361.

It is an arithmetic number, because the mean of its divisors is an integer number (2395004514).

Almost surely, 2^16421878556 is an apocalyptic number.

It is an amenable number.

16421878556 is a deficient number, since it is larger than the sum of its proper divisors (12318175612).

16421878556 is a wasteful number, since it uses less digits than its factorization.

16421878556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252388 (or 252386 counting only the distinct ones).

The product of its digits is 3225600, while the sum is 53.

The spelling of 16421878556 in words is "sixteen billion, four hundred twenty-one million, eight hundred seventy-eight thousand, five hundred fifty-six".