64490666609 has 4 divisors (see below), whose sum is σ = 67884912240. Its totient is φ = 61096420980.

The previous prime is 64490666563. The next prime is 64490666633. The reversal of 64490666609 is 90666609446.

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 not a de Polignac number, because 64490666609 - 2¹² = 64490662513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64490666699) 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, 1697122787 + ... + 1697122824.

It is an arithmetic number, because the mean of its divisors is an integer number (16971228060).

Almost surely, 2^64490666609 is an apocalyptic number.

It is an amenable number.

64490666609 is a deficient number, since it is larger than the sum of its proper divisors (3394245631).

64490666609 is a wasteful number, since it uses less digits than its factorization.

64490666609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3394245630.

The product of its (nonzero) digits is 10077696, while the sum is 56.

The spelling of 64490666609 in words is "sixty-four billion, four hundred ninety million, six hundred sixty-six thousand, six hundred nine".