19897814 has 4 divisors (see below), whose sum is σ = 29846724. Its totient is φ = 9948906.

The previous prime is 19897789. The next prime is 19897847. The reversal of 19897814 is 41879891.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4974452 + ... + 4974455.

It is an arithmetic number, because the mean of its divisors is an integer number (7461681).

Almost surely, 2^19897814 is an apocalyptic number.

19897814 is a deficient number, since it is larger than the sum of its proper divisors (9948910).

19897814 is an equidigital number, since it uses as much as digits as its factorization.

19897814 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9948909.

The product of its digits is 145152, while the sum is 47.

The square root of 19897814 is about 4460.6965823737. The cubic root of 19897814 is about 270.9786796224.

The spelling of 19897814 in words is "nineteen million, eight hundred ninety-seven thousand, eight hundred fourteen".