19400945 has 4 divisors (see below), whose sum is σ = 23281140. Its totient is φ = 15520752.

The previous prime is 19400929. The next prime is 19400951. The reversal of 19400945 is 54900491.

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 4276624 + 15124321 = 2068^2 + 3889^2 .

It is a cyclic number.

It is not a de Polignac number, because 19400945 - 2⁴ = 19400929 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1940090 + ... + 1940099.

It is an arithmetic number, because the mean of its divisors is an integer number (5820285).

Almost surely, 2^19400945 is an apocalyptic number.

It is an amenable number.

19400945 is a deficient number, since it is larger than the sum of its proper divisors (3880195).

19400945 is an equidigital number, since it uses as much as digits as its factorization.

19400945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3880194.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 19400945 is about 4404.6503834016. The cubic root of 19400945 is about 268.7041010492.

The spelling of 19400945 in words is "nineteen million, four hundred thousand, nine hundred forty-five".