64399799 has 2 divisors, whose sum is σ = 64399800. Its totient is φ = 64399798.

The previous prime is 64399789. The next prime is 64399801. The reversal of 64399799 is 99799346.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64399799 is a prime.

It is a super-2 number, since 2×64399799² = 8294668222480802, which contains 22 as substring.

Together with 64399801, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64399789) 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, 32199899 + 32199900.

It is an arithmetic number, because the mean of its divisors is an integer number (32199900).

Almost surely, 2^64399799 is an apocalyptic number.

64399799 is a deficient number, since it is larger than the sum of its proper divisors (1).

64399799 is an equidigital number, since it uses as much as digits as its factorization.

64399799 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3306744, while the sum is 56.

The square root of 64399799 is about 8024.9485356605. The cubic root of 64399799 is about 400.8311862107.

It can be divided in two parts, 6439 and 9799, that multiplied together give a triangular number (63095761 = T₁₁₂₃₃).

The spelling of 64399799 in words is "sixty-four million, three hundred ninety-nine thousand, seven hundred ninety-nine".