19798397 has 4 divisors (see below), whose sum is σ = 19868640. Its totient is φ = 19728156.

The previous prime is 19798381. The next prime is 19798409. The reversal of 19798397 is 79389791.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 19798397 - 2⁴ = 19798381 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19798357) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34697 + ... + 35262.

It is an arithmetic number, because the mean of its divisors is an integer number (4967160).

Almost surely, 2^19798397 is an apocalyptic number.

It is an amenable number.

19798397 is a deficient number, since it is larger than the sum of its proper divisors (70243).

19798397 is an equidigital number, since it uses as much as digits as its factorization.

19798397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70242.

The product of its digits is 857304, while the sum is 53.

The square root of 19798397 is about 4449.5389648816. The cubic root of 19798397 is about 270.5266219301.

The spelling of 19798397 in words is "nineteen million, seven hundred ninety-eight thousand, three hundred ninety-seven".