20915963 has 2 divisors, whose sum is σ = 20915964. Its totient is φ = 20915962.

The previous prime is 20915959. The next prime is 20915969. The reversal of 20915963 is 36951902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20915963 - 2² = 20915959 is a prime.

It is not a weakly prime, because it can be changed into another prime (20915969) 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, 10457981 + 10457982.

It is an arithmetic number, because the mean of its divisors is an integer number (10457982).

Almost surely, 2^20915963 is an apocalyptic number.

20915963 is a deficient number, since it is larger than the sum of its proper divisors (1).

20915963 is an equidigital number, since it uses as much as digits as its factorization.

20915963 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14580, while the sum is 35.

The square root of 20915963 is about 4573.3973149072. The cubic root of 20915963 is about 275.5239070473.

The spelling of 20915963 in words is "twenty million, nine hundred fifteen thousand, nine hundred sixty-three".