19278021216 has 48 divisors (see below), whose sum is σ = 53581563504. Its totient is φ = 6048006144.

The previous prime is 19278021209. The next prime is 19278021221. The reversal of 19278021216 is 61212087291.

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-2 number, since 2×19278021216² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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, 5904625 + ... + 5907888.

It is an arithmetic number, because the mean of its divisors is an integer number (1116282573).

Almost surely, 2^19278021216 is an apocalyptic number.

19278021216 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

19278021216 is an abundant number, since it is smaller than the sum of its proper divisors (34303542288).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19278021216 is a wasteful number, since it uses less digits than its factorization.

19278021216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11812543 (or 11812535 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 39.

The spelling of 19278021216 in words is "nineteen billion, two hundred seventy-eight million, twenty-one thousand, two hundred sixteen".