1643407465 has 16 divisors (see below), whose sum is σ = 2277055872. Its totient is φ = 1115288064.

The previous prime is 1643407453. The next prime is 1643407487. The reversal of 1643407465 is 5647043461.

It is a cyclic number.

It is not a de Polignac number, because 1643407465 - 2²¹ = 1641310313 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 238639 + ... + 245428.

It is an arithmetic number, because the mean of its divisors is an integer number (142315992).

Almost surely, 2^1643407465 is an apocalyptic number.

It is an amenable number.

1643407465 is a deficient number, since it is larger than the sum of its proper divisors (633648407).

1643407465 is an equidigital number, since it uses as much as digits as its factorization.

1643407465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 484176.

The product of its (nonzero) digits is 241920, while the sum is 40.

The square root of 1643407465 is about 40538.9623078835. The cubic root of 1643407465 is about 1180.0898775264.

The spelling of 1643407465 in words is "one billion, six hundred forty-three million, four hundred seven thousand, four hundred sixty-five".