1218917900 has 18 divisors (see below), whose sum is σ = 2645052060. Its totient is φ = 487567120.

The previous prime is 1218917891. The next prime is 1218917929. The reversal of 1218917900 is 97198121.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6094490 + ... + 6094689.

Almost surely, 2^1218917900 is an apocalyptic number.

1218917900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1218917900 is an abundant number, since it is smaller than the sum of its proper divisors (1426134160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1218917900 is a wasteful number, since it uses less digits than its factorization.

1218917900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12189193 (or 12189186 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 38.

The square root of 1218917900 is about 34913.0047403543. The cubic root of 1218917900 is about 1068.2137197545.

The spelling of 1218917900 in words is "one billion, two hundred eighteen million, nine hundred seventeen thousand, nine hundred".