201645823 has 8 divisors (see below), whose sum is σ = 214241328. Its totient is φ = 189131904.

The previous prime is 201645817. The next prime is 201645863. The reversal of 201645823 is 328546102.

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 201645823 - 2¹⁷ = 201514751 is a prime.

It is a super-2 number, since 2×201645823² = 81322075866694658, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201645863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15261 + ... + 25222.

It is an arithmetic number, because the mean of its divisors is an integer number (26780166).

Almost surely, 2^201645823 is an apocalyptic number.

201645823 is a deficient number, since it is larger than the sum of its proper divisors (12595505).

201645823 is a wasteful number, since it uses less digits than its factorization.

201645823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40793.

The product of its (nonzero) digits is 11520, while the sum is 31.

The square root of 201645823 is about 14200.2050337310. The cubic root of 201645823 is about 586.4033059846.

The spelling of 201645823 in words is "two hundred one million, six hundred forty-five thousand, eight hundred twenty-three".