6440266640466 has 12 divisors (see below), whose sum is σ = 13953911054382. Its totient is φ = 2146755546816.

The previous prime is 6440266640429. The next prime is 6440266640491. The reversal of 6440266640466 is 6640466620446.

It can be written as a sum of positive squares in only one way, i.e., 5606140617441 + 834126023025 = 2367729^2 + 913305^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 178896295551 + ... + 178896295586.

Almost surely, 2^{6440266640466} is an apocalyptic number.

6440266640466 is an abundant number, since it is smaller than the sum of its proper divisors (7513644413916).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6440266640466 is a wasteful number, since it uses less digits than its factorization.

6440266640466 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 357792591145 (or 357792591142 counting only the distinct ones).

The product of its (nonzero) digits is 23887872, while the sum is 54.

The spelling of 6440266640466 in words is "six trillion, four hundred forty billion, two hundred sixty-six million, six hundred forty thousand, four hundred sixty-six".