63977746721 has 8 divisors (see below), whose sum is σ = 73132692864. Its totient is φ = 54826617600.

The previous prime is 63977746717. The next prime is 63977746753. The reversal of 63977746721 is 12764777936.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 63977746721 - 2² = 63977746717 is a prime.

It is not an unprimeable number, because it can be changed into a prime (63977746621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 918245 + ... + 985458.

It is an arithmetic number, because the mean of its divisors is an integer number (9141586608).

Almost surely, 2^63977746721 is an apocalyptic number.

It is an amenable number.

63977746721 is a deficient number, since it is larger than the sum of its proper divisors (9154946143).

63977746721 is a wasteful number, since it uses less digits than its factorization.

63977746721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1908511.

The product of its digits is 18670176, while the sum is 59.

The spelling of 63977746721 in words is "sixty-three billion, nine hundred seventy-seven million, seven hundred forty-six thousand, seven hundred twenty-one".