19740689 has 4 divisors (see below), whose sum is σ = 20901924. Its totient is φ = 18579456.

The previous prime is 19740667. The next prime is 19740691. The reversal of 19740689 is 98604791.

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

It can be written as a sum of positive squares in 2 ways, for example, as 12902464 + 6838225 = 3592^2 + 2615^2 .

It is a cyclic number.

It is not a de Polignac number, because 19740689 - 2¹² = 19736593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19740649) 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, 580592 + ... + 580625.

It is an arithmetic number, because the mean of its divisors is an integer number (5225481).

Almost surely, 2^19740689 is an apocalyptic number.

It is an amenable number.

19740689 is a deficient number, since it is larger than the sum of its proper divisors (1161235).

19740689 is a wasteful number, since it uses less digits than its factorization.

19740689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1161234.

The product of its (nonzero) digits is 108864, while the sum is 44.

The square root of 19740689 is about 4443.0495158168. The cubic root of 19740689 is about 270.2635241485.

The spelling of 19740689 in words is "nineteen million, seven hundred forty thousand, six hundred eighty-nine".