19678871 has 4 divisors (see below), whose sum is σ = 19870032. Its totient is φ = 19487712.

The previous prime is 19678807. The next prime is 19678873. The reversal of 19678871 is 17887691.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17887691 = 1151 ⋅15541.

It is a cyclic number.

It is not a de Polignac number, because 19678871 - 2⁶ = 19678807 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19678873) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 95426 + ... + 95631.

It is an arithmetic number, because the mean of its divisors is an integer number (4967508).

Almost surely, 2^19678871 is an apocalyptic number.

19678871 is a deficient number, since it is larger than the sum of its proper divisors (191161).

19678871 is a wasteful number, since it uses less digits than its factorization.

19678871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191160.

The product of its digits is 169344, while the sum is 47.

The square root of 19678871 is about 4436.0873526115. The cubic root of 19678871 is about 269.9811189357.

The spelling of 19678871 in words is "nineteen million, six hundred seventy-eight thousand, eight hundred seventy-one".