1818561494 has 16 divisors (see below), whose sum is σ = 2818452480. Its totient is φ = 879131880.

The previous prime is 1818561487. The next prime is 1818561509. The reversal of 1818561494 is 4941658181.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56567 + ... + 82685.

It is an arithmetic number, because the mean of its divisors is an integer number (176153280).

Almost surely, 2^1818561494 is an apocalyptic number.

1818561494 is a deficient number, since it is larger than the sum of its proper divisors (999890986).

1818561494 is a wasteful number, since it uses less digits than its factorization.

1818561494 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27275.

The product of its digits is 276480, while the sum is 47.

The square root of 1818561494 is about 42644.5951323260. The cubic root of 1818561494 is about 1220.6073957479.

The spelling of 1818561494 in words is "one billion, eight hundred eighteen million, five hundred sixty-one thousand, four hundred ninety-four".