20355845 has 8 divisors (see below), whose sum is σ = 24456600. Its totient is φ = 16264960.

The previous prime is 20355827. The next prime is 20355847. The reversal of 20355845 is 54855302.

It can be written as a sum of positive squares in 4 ways, for example, as 6974881 + 13380964 = 2641^2 + 3658^2 .

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

It is not a de Polignac number, because 20355845 - 2⁶ = 20355781 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20355847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3305 + ... + 7185.

It is an arithmetic number, because the mean of its divisors is an integer number (3057075).

Almost surely, 2^20355845 is an apocalyptic number.

It is an amenable number.

20355845 is a deficient number, since it is larger than the sum of its proper divisors (4100755).

20355845 is a wasteful number, since it uses less digits than its factorization.

20355845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4935.

The product of its (nonzero) digits is 24000, while the sum is 32.

The square root of 20355845 is about 4511.7452277362. The cubic root of 20355845 is about 273.0421605198.

The spelling of 20355845 in words is "twenty million, three hundred fifty-five thousand, eight hundred forty-five".