20538949 has 2 divisors, whose sum is σ = 20538950. Its totient is φ = 20538948.

The previous prime is 20538937. The next prime is 20538967. The reversal of 20538949 is 94983502.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15444900 + 5094049 = 3930^2 + 2257^2 .

It is a cyclic number.

It is not a de Polignac number, because 20538949 - 2⁹ = 20538437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20538919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10269474 + 10269475.

It is an arithmetic number, because the mean of its divisors is an integer number (10269475).

Almost surely, 2^20538949 is an apocalyptic number.

It is an amenable number.

20538949 is a deficient number, since it is larger than the sum of its proper divisors (1).

20538949 is an equidigital number, since it uses as much as digits as its factorization.

20538949 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 77760, while the sum is 40.

The square root of 20538949 is about 4531.9917254999. The cubic root of 20538949 is about 273.8584035826.

The spelling of 20538949 in words is "twenty million, five hundred thirty-eight thousand, nine hundred forty-nine".