20155243 has 4 divisors (see below), whose sum is σ = 20166840. Its totient is φ = 20143648.

The previous prime is 20155169. The next prime is 20155249. The reversal of 20155243 is 34255102.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20155243 - 2²¹ = 18058091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20155249) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2605 + ... + 6862.

It is an arithmetic number, because the mean of its divisors is an integer number (5041710).

Almost surely, 2^20155243 is an apocalyptic number.

20155243 is a deficient number, since it is larger than the sum of its proper divisors (11597).

20155243 is an equidigital number, since it uses as much as digits as its factorization.

20155243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11596.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 20155243 is about 4489.4590988225. The cubic root of 20155243 is about 272.1422761644.

The spelling of 20155243 in words is "twenty million, one hundred fifty-five thousand, two hundred forty-three".