1781806012 has 18 divisors (see below), whose sum is σ = 3627248352. Its totient is φ = 763631064.

The previous prime is 1781805979. The next prime is 1781806027. The reversal of 1781806012 is 2106081871.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4545228 + ... + 4545619.

Almost surely, 2^1781806012 is an apocalyptic number.

It is an amenable number.

1781806012 is an abundant number, since it is smaller than the sum of its proper divisors (1845442340).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1781806012 is a wasteful number, since it uses less digits than its factorization.

1781806012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9090865 (or 9090856 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 34.

The square root of 1781806012 is about 42211.4440880669. Note that the first 3 decimals coincide. The cubic root of 1781806012 is about 1212.3280117693.

Adding to 1781806012 its reverse (2106081871), we get a palindrome (3887887883).

The spelling of 1781806012 in words is "one billion, seven hundred eighty-one million, eight hundred six thousand, twelve".