1643696064 has 70 divisors (see below), whose sum is σ = 4872445424. Its totient is φ = 547896960.

The previous prime is 1643696011. The next prime is 1643696069. The reversal of 1643696064 is 4606963461.

1643696064 is a `hidden beast` number, since 1 + 6 + 4 + 36 + 9 + 606 + 4 = 666.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643696069) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 153352 + ... + 163719.

Almost surely, 2^1643696064 is an apocalyptic number.

It is an amenable number.

1643696064 is an abundant number, since it is smaller than the sum of its proper divisors (3228749360).

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

1643696064 is an equidigital number, since it uses as much as digits as its factorization.

1643696064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317095 (or 317076 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 45.

The square root of 1643696064 is about 40542.5216778631. The cubic root of 1643696064 is about 1180.1589520624.

The spelling of 1643696064 in words is "one billion, six hundred forty-three million, six hundred ninety-six thousand, sixty-four".