19681634 has 24 divisors (see below), whose sum is σ = 34531740. Its totient is φ = 8388576.

The previous prime is 19681609. The next prime is 19681637. The reversal of 19681634 is 43618691.

It can be written as a sum of positive squares in 2 ways, for example, as 15976009 + 3705625 = 3997^2 + 1925^2 .

It is not an unprimeable number, because it can be changed into a prime (19681637) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22004 + ... + 22880.

Almost surely, 2^19681634 is an apocalyptic number.

19681634 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

19681634 is a deficient number, since it is larger than the sum of its proper divisors (14850106).

19681634 is a wasteful number, since it uses less digits than its factorization.

19681634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1122 (or 1115 counting only the distinct ones).

The product of its digits is 31104, while the sum is 38.

The square root of 19681634 is about 4436.3987647641. The cubic root of 19681634 is about 269.9937538564.

The spelling of 19681634 in words is "nineteen million, six hundred eighty-one thousand, six hundred thirty-four".