1645677893729 has 4 divisors (see below), whose sum is σ = 1645740202176. Its totient is φ = 1645615585284.

The previous prime is 1645677893701. The next prime is 1645677893767. The reversal of 1645677893729 is 9273987765461.

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 1645677893729 - 2³⁶ = 1576958416993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1645677893789) 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, 31114589 + ... + 31167434.

It is an arithmetic number, because the mean of its divisors is an integer number (411435050544).

Almost surely, 2^{1645677893729} is an apocalyptic number.

It is an amenable number.

1645677893729 is a deficient number, since it is larger than the sum of its proper divisors (62308447).

1645677893729 is an equidigital number, since it uses as much as digits as its factorization.

1645677893729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62308446.

The product of its digits is 960180480, while the sum is 74.

The spelling of 1645677893729 in words is "one trillion, six hundred forty-five billion, six hundred seventy-seven million, eight hundred ninety-three thousand, seven hundred twenty-nine".