64439693 has 2 divisors, whose sum is σ = 64439694. Its totient is φ = 64439692.

The previous prime is 64439689. The next prime is 64439699. The reversal of 64439693 is 39693446.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 56220004 + 8219689 = 7498^2 + 2867^2 .

It is a cyclic number.

It is not a de Polignac number, because 64439693 - 2² = 64439689 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64439699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32219846 + 32219847.

It is an arithmetic number, because the mean of its divisors is an integer number (32219847).

Almost surely, 2^64439693 is an apocalyptic number.

It is an amenable number.

64439693 is a deficient number, since it is larger than the sum of its proper divisors (1).

64439693 is an equidigital number, since it uses as much as digits as its factorization.

64439693 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 419904, while the sum is 44.

The square root of 64439693 is about 8027.4337742519. The cubic root of 64439693 is about 400.9139372895.

The spelling of 64439693 in words is "sixty-four million, four hundred thirty-nine thousand, six hundred ninety-three".