1803955729 has 3 divisors (see below), whose sum is σ = 1803998203. Its totient is φ = 1803913256.

The previous prime is 1803955709. The next prime is 1803955763. The reversal of 1803955729 is 9275593081.

The square root of 1803955729 is 42473.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 302238225 + 1501717504 = 17385^2 + 38752^2 .

It is not a de Polignac number, because 1803955729 - 2¹¹ = 1803953681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1803955709) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 21237 + ... + 63709.

Almost surely, 2^1803955729 is an apocalyptic number.

1803955729 is the 42473-rd square number.

1803955729 is the 21237-th centered octagonal number.

It is an amenable number.

1803955729 is a deficient number, since it is larger than the sum of its proper divisors (42474).

1803955729 is an frugal number, since it uses more digits than its factorization.

1803955729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84946 (or 42473 counting only the distinct ones).

The product of its (nonzero) digits is 680400, while the sum is 49.

The cubic root of 1803955729 is about 1217.3308413246.

Multiplying 1803955729 by its sum of digits (49), we get a square (88393830721 = 297311²).

The spelling of 1803955729 in words is "one billion, eight hundred three million, nine hundred fifty-five thousand, seven hundred twenty-nine".