1816982261 has 4 divisors (see below), whose sum is σ = 1875594624. Its totient is φ = 1758369900.

The previous prime is 1816982227. The next prime is 1816982291. The reversal of 1816982261 is 1622896181.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1816982261 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 (1816982291) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29306135 + ... + 29306196.

It is an arithmetic number, because the mean of its divisors is an integer number (468898656).

Almost surely, 2^1816982261 is an apocalyptic number.

It is an amenable number.

1816982261 is a deficient number, since it is larger than the sum of its proper divisors (58612363).

1816982261 is an equidigital number, since it uses as much as digits as its factorization.

1816982261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58612362.

The product of its digits is 82944, while the sum is 44.

The square root of 1816982261 is about 42626.0748955378. The cubic root of 1816982261 is about 1220.2539695672.

The spelling of 1816982261 in words is "one billion, eight hundred sixteen million, nine hundred eighty-two thousand, two hundred sixty-one".