18969397 has 4 divisors (see below), whose sum is σ = 18993996. Its totient is φ = 18944800.

The previous prime is 18969383. The next prime is 18969403. The reversal of 18969397 is 79396981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 79396981 = 191 ⋅415691.

It can be written as a sum of positive squares in 2 ways, for example, as 11792356 + 7177041 = 3434^2 + 2679^2 .

It is a cyclic number.

It is not a de Polignac number, because 18969397 - 2¹¹ = 18967349 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 (18969317) 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, 11104 + ... + 12697.

It is an arithmetic number, because the mean of its divisors is an integer number (4748499).

Almost surely, 2^18969397 is an apocalyptic number.

It is an amenable number.

18969397 is a deficient number, since it is larger than the sum of its proper divisors (24599).

18969397 is an equidigital number, since it uses as much as digits as its factorization.

18969397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24598.

The product of its digits is 734832, while the sum is 52.

The square root of 18969397 is about 4355.3871240109. The cubic root of 18969397 is about 266.6968228049.

The spelling of 18969397 in words is "eighteen million, nine hundred sixty-nine thousand, three hundred ninety-seven".