63999121 has 2 divisors, whose sum is σ = 63999122. Its totient is φ = 63999120.

The previous prime is 63999083. The next prime is 63999127. The reversal of 63999121 is 12199936.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63123025 + 876096 = 7945^2 + 936^2 .

It is a cyclic number.

It is not a de Polignac number, because 63999121 - 2¹³ = 63990929 is a prime.

It is not a weakly prime, because it can be changed into another prime (63999127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31999560 + 31999561.

It is an arithmetic number, because the mean of its divisors is an integer number (31999561).

Almost surely, 2^63999121 is an apocalyptic number.

It is an amenable number.

63999121 is a deficient number, since it is larger than the sum of its proper divisors (1).

63999121 is an equidigital number, since it uses as much as digits as its factorization.

63999121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26244, while the sum is 40.

The square root of 63999121 is about 7999.9450623114. The cubic root of 63999121 is about 399.9981687416.

The spelling of 63999121 in words is "sixty-three million, nine hundred ninety-nine thousand, one hundred twenty-one".