19978914 has 8 divisors (see below), whose sum is σ = 39957840. Its totient is φ = 6659636.

The previous prime is 19978897. The next prime is 19978919. The reversal of 19978914 is 41987991.

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

19978914 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (19978919) 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 3 ways as a sum of consecutive naturals, for example, 1664904 + ... + 1664915.

It is an arithmetic number, because the mean of its divisors is an integer number (4994730).

Almost surely, 2^19978914 is an apocalyptic number.

19978914 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

19978914 is a wasteful number, since it uses less digits than its factorization.

19978914 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3329824.

The product of its digits is 163296, while the sum is 48.

The square root of 19978914 is about 4469.7778468286. Note that the first 3 decimals coincide. The cubic root of 19978914 is about 271.3463344322.

The spelling of 19978914 in words is "nineteen million, nine hundred seventy-eight thousand, nine hundred fourteen".