19800071 has 4 divisors (see below), whose sum is σ = 20842200. Its totient is φ = 18757944.

The previous prime is 19799993. The next prime is 19800083. The reversal of 19800071 is 17000891.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 19800071 - 2²² = 15605767 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19800071.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19800271) 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, 521036 + ... + 521073.

It is an arithmetic number, because the mean of its divisors is an integer number (5210550).

Almost surely, 2^19800071 is an apocalyptic number.

19800071 is a deficient number, since it is larger than the sum of its proper divisors (1042129).

19800071 is a wasteful number, since it uses less digits than its factorization.

19800071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1042128.

The product of its (nonzero) digits is 504, while the sum is 26.

The square root of 19800071 is about 4449.7270702820. The cubic root of 19800071 is about 270.5342462646.

The spelling of 19800071 in words is "nineteen million, eight hundred thousand, seventy-one".