19640745 has 16 divisors (see below), whose sum is σ = 34917120. Its totient is φ = 10474992.

The previous prime is 19640741. The next prime is 19640749. The reversal of 19640745 is 54704691.

19640745 is a `hidden beast` number, since 1 + 9 + 640 + 7 + 4 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (19640741) and next prime (19640749).

It is not a de Polignac number, because 19640745 - 2² = 19640741 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (19640741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 72609 + ... + 72878.

It is an arithmetic number, because the mean of its divisors is an integer number (2182320).

Almost surely, 2^19640745 is an apocalyptic number.

19640745 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

19640745 is a deficient number, since it is larger than the sum of its proper divisors (15276375).

19640745 is a wasteful number, since it uses less digits than its factorization.

19640745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145501 (or 145495 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 19640745 is about 4431.7880138833. The cubic root of 19640745 is about 269.8066516989.

The spelling of 19640745 in words is "nineteen million, six hundred forty thousand, seven hundred forty-five".