19782097 has 4 divisors (see below), whose sum is σ = 20823280. Its totient is φ = 18740916.

The previous prime is 19782079. The next prime is 19782109. The reversal of 19782097 is 79028791.

It is a happy number.

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 not a de Polignac number, because 19782097 - 2⁷ = 19781969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19782017) 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, 520563 + ... + 520600.

It is an arithmetic number, because the mean of its divisors is an integer number (5205820).

Almost surely, 2^19782097 is an apocalyptic number.

It is an amenable number.

19782097 is a deficient number, since it is larger than the sum of its proper divisors (1041183).

19782097 is a wasteful number, since it uses less digits than its factorization.

19782097 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1041182.

The product of its (nonzero) digits is 63504, while the sum is 43.

The square root of 19782097 is about 4447.7069372880. The cubic root of 19782097 is about 270.4523601161.

The spelling of 19782097 in words is "nineteen million, seven hundred eighty-two thousand, ninety-seven".