19978116 has 24 divisors (see below), whose sum is σ = 46986240. Its totient is φ = 6606432.

The previous prime is 19978109. The next prime is 19978117. The reversal of 19978116 is 61187991.

It is not an unprimeable number, because it can be changed into a prime (19978117) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5031 + ... + 8078.

It is an arithmetic number, because the mean of its divisors is an integer number (1957760).

Almost surely, 2^19978116 is an apocalyptic number.

It is an amenable number.

19978116 is an abundant number, since it is smaller than the sum of its proper divisors (27008124).

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

19978116 is a wasteful number, since it uses less digits than its factorization.

19978116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13243 (or 13241 counting only the distinct ones).

The product of its digits is 27216, while the sum is 42.

The square root of 19978116 is about 4469.6885797559. The cubic root of 19978116 is about 271.3427216690.

The spelling of 19978116 in words is "nineteen million, nine hundred seventy-eight thousand, one hundred sixteen".