1645864829 has 4 divisors (see below), whose sum is σ = 1880988384. Its totient is φ = 1410741276.

The previous prime is 1645864771. The next prime is 1645864837. The reversal of 1645864829 is 9284685461.

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 not a de Polignac number, because 1645864829 - 2⁸ = 1645864573 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645864859) 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, 117561767 + ... + 117561780.

It is an arithmetic number, because the mean of its divisors is an integer number (470247096).

Almost surely, 2^1645864829 is an apocalyptic number.

It is an amenable number.

1645864829 is a deficient number, since it is larger than the sum of its proper divisors (235123555).

1645864829 is an equidigital number, since it uses as much as digits as its factorization.

1645864829 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235123554.

The product of its digits is 3317760, while the sum is 53.

The square root of 1645864829 is about 40569.2596555569. The cubic root of 1645864829 is about 1180.6777751811.

The spelling of 1645864829 in words is "one billion, six hundred forty-five million, eight hundred sixty-four thousand, eight hundred twenty-nine".