19812145 has 8 divisors (see below), whose sum is σ = 24280704. Its totient is φ = 15512304.

The previous prime is 19812113. The next prime is 19812179. The reversal of 19812145 is 54121891.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19812145 - 2⁵ = 19812113 is a prime.

It is a super-3 number, since 3×19812145³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 41919 + ... + 42388.

It is an arithmetic number, because the mean of its divisors is an integer number (3035088).

Almost surely, 2^19812145 is an apocalyptic number.

It is an amenable number.

19812145 is a deficient number, since it is larger than the sum of its proper divisors (4468559).

19812145 is an equidigital number, since it uses as much as digits as its factorization.

19812145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84359.

The product of its digits is 2880, while the sum is 31.

The square root of 19812145 is about 4451.0835759397. The cubic root of 19812145 is about 270.5892253059.

The spelling of 19812145 in words is "nineteen million, eight hundred twelve thousand, one hundred forty-five".