19897842 has 16 divisors (see below), whose sum is σ = 39840480. Its totient is φ = 6625152.

The previous prime is 19897789. The next prime is 19897847. The reversal of 19897842 is 24879891.

It is a junction number, because it is equal to n+sod(n) for n = 19897791 and 19897800.

It is not an unprimeable number, because it can be changed into a prime (19897847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7618 + ... + 9890.

It is an arithmetic number, because the mean of its divisors is an integer number (2490030).

Almost surely, 2^19897842 is an apocalyptic number.

19897842 is an abundant number, since it is smaller than the sum of its proper divisors (19942638).

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

19897842 is a wasteful number, since it uses less digits than its factorization.

19897842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3737.

The product of its digits is 290304, while the sum is 48.

The square root of 19897842 is about 4460.6997208958. The cubic root of 19897842 is about 270.9788067285.

The spelling of 19897842 in words is "nineteen million, eight hundred ninety-seven thousand, eight hundred forty-two".