19870 has 8 divisors (see below), whose sum is σ = 35784. Its totient is φ = 7944.

The previous prime is 19867. The next prime is 19889. The reversal of 19870 is 7891.

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

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, 984 + ... + 1003.

It is an arithmetic number, because the mean of its divisors is an integer number (4473).

2¹⁹⁸⁷⁰ is an apocalyptic number.

19870 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19870 is a deficient number, since it is larger than the sum of its proper divisors (15914).

19870 is a wasteful number, since it uses less digits than its factorization.

19870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1994.

The product of its (nonzero) digits is 504, while the sum is 25.

The square root of 19870 is about 140.9609875107. The cubic root of 19870 is about 27.0852358953.

The spelling of 19870 in words is "nineteen thousand, eight hundred seventy".