1812780993 has 8 divisors (see below), whose sum is σ = 2419058656. Its totient is φ = 1207512000.

The previous prime is 1812780979. The next prime is 1812781037. The reversal of 1812780993 is 3990872181.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1812780993 - 2⁵ = 1812780961 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1812780943) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 247963 + ... + 255168.

It is an arithmetic number, because the mean of its divisors is an integer number (302382332).

Almost surely, 2^1812780993 is an apocalyptic number.

It is an amenable number.

1812780993 is a deficient number, since it is larger than the sum of its proper divisors (606277663).

1812780993 is a wasteful number, since it uses less digits than its factorization.

1812780993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 504335.

The product of its (nonzero) digits is 217728, while the sum is 48.

The square root of 1812780993 is about 42576.7658823448. The cubic root of 1812780993 is about 1219.3127440273.

The spelling of 1812780993 in words is "one billion, eight hundred twelve million, seven hundred eighty thousand, nine hundred ninety-three".