20545434 has 128 divisors (see below), whose sum is σ = 58222080. Its totient is φ = 5225472.

The previous prime is 20545433. The next prime is 20545477. The reversal of 20545434 is 43454502.

20545434 is a `hidden beast` number, since 205 + 454 + 3 + 4 = 666.

It is a super-2 number, since 2×20545434² = 844229716496712, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 20545398 and 20545407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20545433) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 181762 + ... + 181874.

It is an arithmetic number, because the mean of its divisors is an integer number (454860).

Almost surely, 2^20545434 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20545434, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29111040).

20545434 is an abundant number, since it is smaller than the sum of its proper divisors (37676646).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20545434 is a wasteful number, since it uses less digits than its factorization.

20545434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181 (or 175 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 27.

The square root of 20545434 is about 4532.7071381240. The cubic root of 20545434 is about 273.8872233771.

Adding to 20545434 its reverse (43454502), we get a palindrome (63999936).

The spelling of 20545434 in words is "twenty million, five hundred forty-five thousand, four hundred thirty-four".