20945538 has 12 divisors (see below), whose sum is σ = 45382038. Its totient is φ = 6981840.

The previous prime is 20945537. The next prime is 20945563. The reversal of 20945538 is 83554902.

It can be written as a sum of positive squares in only one way, i.e., 16136289 + 4809249 = 4017^2 + 2193^2 .

It is not an unprimeable number, because it can be changed into a prime (20945537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 581803 + ... + 581838.

Almost surely, 2^20945538 is an apocalyptic number.

20945538 is an abundant number, since it is smaller than the sum of its proper divisors (24436500).

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

20945538 is a wasteful number, since it uses less digits than its factorization.

20945538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1163649 (or 1163646 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The square root of 20945538 is about 4576.6295458558. The cubic root of 20945538 is about 275.6537087347.

The spelling of 20945538 in words is "twenty million, nine hundred forty-five thousand, five hundred thirty-eight".