1812716991 has 12 divisors (see below), whose sum is σ = 2632837480. Its totient is φ = 1201800240.

The previous prime is 1812716981. The next prime is 1812717029. The reversal of 1812716991 is 1996172181.

It is a happy number.

It is not a de Polignac number, because 1812716991 - 2¹⁴ = 1812700607 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1812716911) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 554761 + ... + 558018.

Almost surely, 2^1812716991 is an apocalyptic number.

1812716991 is a deficient number, since it is larger than the sum of its proper divisors (820120489).

1812716991 is a wasteful number, since it uses less digits than its factorization.

1812716991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1112966 (or 1112963 counting only the distinct ones).

The product of its digits is 54432, while the sum is 45.

The square root of 1812716991 is about 42576.0142685996. The cubic root of 1812716991 is about 1219.2983941834.

It can be divided in two parts, 181 and 2716991, that added together give a palindrome (2717172).

The spelling of 1812716991 in words is "one billion, eight hundred twelve million, seven hundred sixteen thousand, nine hundred ninety-one".