20438161 has 2 divisors, whose sum is σ = 20438162. Its totient is φ = 20438160.

The previous prime is 20438147. The next prime is 20438179. The reversal of 20438161 is 16183402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13838400 + 6599761 = 3720^2 + 2569^2 .

It is a cyclic number.

It is not a de Polignac number, because 20438161 - 2¹¹ = 20436113 is a prime.

It is not a weakly prime, because it can be changed into another prime (20432161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10219080 + 10219081.

It is an arithmetic number, because the mean of its divisors is an integer number (10219081).

Almost surely, 2^20438161 is an apocalyptic number.

It is an amenable number.

20438161 is a deficient number, since it is larger than the sum of its proper divisors (1).

20438161 is an equidigital number, since it uses as much as digits as its factorization.

20438161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 20438161 is about 4520.8584361822. The cubic root of 20438161 is about 273.4097127747.

The spelling of 20438161 in words is "twenty million, four hundred thirty-eight thousand, one hundred sixty-one".