19985213 has 4 divisors (see below), whose sum is σ = 19997628. Its totient is φ = 19972800.

The previous prime is 19985209. The next prime is 19985219. The reversal of 19985213 is 31258991.

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

It can be written as a sum of positive squares in 2 ways, for example, as 466489 + 19518724 = 683^2 + 4418^2 .

It is a cyclic number.

It is not a de Polignac number, because 19985213 - 2² = 19985209 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 (19985219) 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, 3356 + ... + 7157.

It is an arithmetic number, because the mean of its divisors is an integer number (4999407).

Almost surely, 2^19985213 is an apocalyptic number.

It is an amenable number.

19985213 is a deficient number, since it is larger than the sum of its proper divisors (12415).

19985213 is a wasteful number, since it uses less digits than its factorization.

19985213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12414.

The product of its digits is 19440, while the sum is 38.

The square root of 19985213 is about 4470.4824124472. The cubic root of 19985213 is about 271.3748483438.

The spelling of 19985213 in words is "nineteen million, nine hundred eighty-five thousand, two hundred thirteen".