19897938 has 12 divisors (see below), whose sum is σ = 43112238. Its totient is φ = 6632640.

The previous prime is 19897937. The next prime is 19897951. The reversal of 19897938 is 83979891.

It can be written as a sum of positive squares in only one way, i.e., 17918289 + 1979649 = 4233^2 + 1407^2 .

It is not an unprimeable number, because it can be changed into a prime (19897937) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 552703 + ... + 552738.

Almost surely, 2^19897938 is an apocalyptic number.

19897938 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

19897938 is an abundant number, since it is smaller than the sum of its proper divisors (23214300).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19897938 is a wasteful number, since it uses less digits than its factorization.

19897938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1105449 (or 1105446 counting only the distinct ones).

The product of its digits is 979776, while the sum is 54.

The square root of 19897938 is about 4460.7104815265. The cubic root of 19897938 is about 270.9792425199.

The spelling of 19897938 in words is "nineteen million, eight hundred ninety-seven thousand, nine hundred thirty-eight".