1780249249 has 3 divisors (see below), whose sum is σ = 1780291443. Its totient is φ = 1780207056.

The previous prime is 1780249241. The next prime is 1780249253. The reversal of 1780249249 is 9429420871.

The square root of 1780249249 is 42193.

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., 994456225 + 785793024 = 31535^2 + 28032^2 .

It is not a de Polignac number, because 1780249249 - 2³ = 1780249241 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1780249199 and 1780249208.

It is not an unprimeable number, because it can be changed into a prime (1780249241) 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, 21097 + ... + 63289.

It is an arithmetic number, because the mean of its divisors is an integer number (593430481).

Almost surely, 2^1780249249 is an apocalyptic number.

1780249249 is the 42193-rd square number.

1780249249 is the 21097-th centered octagonal number.

It is an amenable number.

1780249249 is a deficient number, since it is larger than the sum of its proper divisors (42194).

1780249249 is an frugal number, since it uses more digits than its factorization.

1780249249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84386 (or 42193 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 46.

The cubic root of 1780249249 is about 1211.9748387726.

The spelling of 1780249249 in words is "one billion, seven hundred eighty million, two hundred forty-nine thousand, two hundred forty-nine".