1864442729 has 4 divisors (see below), whose sum is σ = 1882902660. Its totient is φ = 1845982800.

The previous prime is 1864442707. The next prime is 1864442743. The reversal of 1864442729 is 9272444681.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9272444681 = 37 ⋅250606613.

It can be written as a sum of positive squares in 2 ways, for example, as 1424911504 + 439531225 = 37748^2 + 20965^2 .

It is a cyclic number.

It is not a de Polignac number, because 1864442729 - 2²⁴ = 1847665513 is a prime.

It is a super-2 number, since 2×1864442729² = 6952293379441934882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1864442029) 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, 9229814 + ... + 9230015.

It is an arithmetic number, because the mean of its divisors is an integer number (470725665).

Almost surely, 2^1864442729 is an apocalyptic number.

It is an amenable number.

1864442729 is a deficient number, since it is larger than the sum of its proper divisors (18459931).

1864442729 is a wasteful number, since it uses less digits than its factorization.

1864442729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18459930.

The product of its digits is 774144, while the sum is 47.

The square root of 1864442729 is about 43179.1932416529. The cubic root of 1864442729 is about 1230.7873270189.

The spelling of 1864442729 in words is "one billion, eight hundred sixty-four million, four hundred forty-two thousand, seven hundred twenty-nine".