63994443757 has 4 divisors (see below), whose sum is σ = 65724023356. Its totient is φ = 62264864160.

The previous prime is 63994443749. The next prime is 63994443763. The reversal of 63994443757 is 75734449936.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 60880134121 + 3114309636 = 246739^2 + 55806^2 .

It is a cyclic number.

It is not a de Polignac number, because 63994443757 - 2³ = 63994443749 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 63994443695 and 63994443704.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63994443707) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 864789744 + ... + 864789817.

It is an arithmetic number, because the mean of its divisors is an integer number (16431005839).

Almost surely, 2^63994443757 is an apocalyptic number.

It is an amenable number.

63994443757 is a deficient number, since it is larger than the sum of its proper divisors (1729579599).

63994443757 is a wasteful number, since it uses less digits than its factorization.

63994443757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1729579598.

The product of its digits is 68584320, while the sum is 61.

The spelling of 63994443757 in words is "sixty-three billion, nine hundred ninety-four million, four hundred forty-three thousand, seven hundred fifty-seven".