19891963 has 16 divisors (see below), whose sum is σ = 24801280. Its totient is φ = 15533856.

The previous prime is 19891961. The next prime is 19891967. The reversal of 19891963 is 36919891.

It is not a de Polignac number, because 19891963 - 2¹ = 19891961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19891961) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5806 + ... + 8572.

It is an arithmetic number, because the mean of its divisors is an integer number (1550080).

Almost surely, 2^19891963 is an apocalyptic number.

19891963 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

19891963 is a deficient number, since it is larger than the sum of its proper divisors (4909317).

19891963 is a wasteful number, since it uses less digits than its factorization.

19891963 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2866.

The product of its digits is 104976, while the sum is 46.

The square root of 19891963 is about 4460.0406948816. The cubic root of 19891963 is about 270.9521163747.

The spelling of 19891963 in words is "nineteen million, eight hundred ninety-one thousand, nine hundred sixty-three".