1218167644 has 24 divisors (see below), whose sum is σ = 2176615280. Its totient is φ = 596398464.

The previous prime is 1218167627. The next prime is 1218167647. The reversal of 1218167644 is 4467618121.

It is a junction number, because it is equal to n+sod(n) for n = 1218167597 and 1218167606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1218167647) 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, 25582 + ... + 55594.

Almost surely, 2^1218167644 is an apocalyptic number.

It is an amenable number.

1218167644 is a deficient number, since it is larger than the sum of its proper divisors (958447636).

1218167644 is a wasteful number, since it uses less digits than its factorization.

1218167644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30229 (or 30227 counting only the distinct ones).

The product of its digits is 64512, while the sum is 40.

The square root of 1218167644 is about 34902.2584369551. The cubic root of 1218167644 is about 1067.9945094099.

The spelling of 1218167644 in words is "one billion, two hundred eighteen million, one hundred sixty-seven thousand, six hundred forty-four".