20634479 has 2 divisors, whose sum is σ = 20634480. Its totient is φ = 20634478.

The previous prime is 20634469. The next prime is 20634487. The reversal of 20634479 is 97443602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20634479 - 2¹⁶ = 20568943 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20634469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10317239 + 10317240.

It is an arithmetic number, because the mean of its divisors is an integer number (10317240).

Almost surely, 2^20634479 is an apocalyptic number.

20634479 is a deficient number, since it is larger than the sum of its proper divisors (1).

20634479 is an equidigital number, since it uses as much as digits as its factorization.

20634479 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 35.

The square root of 20634479 is about 4542.5190148199. The cubic root of 20634479 is about 274.2823336973.

The spelling of 20634479 in words is "twenty million, six hundred thirty-four thousand, four hundred seventy-nine".