1645990327 has 4 divisors (see below), whose sum is σ = 1648511640. Its totient is φ = 1643469016.

The previous prime is 1645990301. The next prime is 1645990351. The reversal of 1645990327 is 7230995461.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1645990327 - 2²⁷ = 1511772599 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645990627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1259677 + ... + 1260982.

It is an arithmetic number, because the mean of its divisors is an integer number (412127910).

Almost surely, 2^1645990327 is an apocalyptic number.

1645990327 is a deficient number, since it is larger than the sum of its proper divisors (2521313).

1645990327 is an equidigital number, since it uses as much as digits as its factorization.

1645990327 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2521312.

The product of its (nonzero) digits is 408240, while the sum is 46.

The square root of 1645990327 is about 40570.8063390414. The cubic root of 1645990327 is about 1180.7077835047.

The spelling of 1645990327 in words is "one billion, six hundred forty-five million, nine hundred ninety thousand, three hundred twenty-seven".