1816121434 has 4 divisors (see below), whose sum is σ = 2724182154. Its totient is φ = 908060716.

The previous prime is 1816121429. The next prime is 1816121467. The reversal of 1816121434 is 4341216181.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1502725225 + 313396209 = 38765^2 + 17703^2 .

It is an alternating number because its digits alternate between odd and even.

It is a junction number, because it is equal to n+sod(n) for n = 1816121396 and 1816121405.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 454030357 + ... + 454030360.

Almost surely, 2^1816121434 is an apocalyptic number.

1816121434 is a deficient number, since it is larger than the sum of its proper divisors (908060720).

1816121434 is an equidigital number, since it uses as much as digits as its factorization.

1816121434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 908060719.

The product of its digits is 4608, while the sum is 31.

The square root of 1816121434 is about 42615.9762765093. The cubic root of 1816121434 is about 1220.0612336013.

The spelling of 1816121434 in words is "one billion, eight hundred sixteen million, one hundred twenty-one thousand, four hundred thirty-four".