64403366666521 has 4 divisors (see below), whose sum is σ = 64404568028944. Its totient is φ = 64402165304100.

The previous prime is 64403366666501. The next prime is 64403366666579. The reversal of 64403366666521 is 12566666330446.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64403366666521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64403366666501) 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, 600600795 + ... + 600708016.

It is an arithmetic number, because the mean of its divisors is an integer number (16101142007236).

Almost surely, 2^{64403366666521} is an apocalyptic number.

It is an amenable number.

64403366666521 is a deficient number, since it is larger than the sum of its proper divisors (1201362423).

64403366666521 is a wasteful number, since it uses less digits than its factorization.

64403366666521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1201362422.

The product of its (nonzero) digits is 67184640, while the sum is 58.

The spelling of 64403366666521 in words is "sixty-four trillion, four hundred three billion, three hundred sixty-six million, six hundred sixty-six thousand, five hundred twenty-one".