1218856353 has 48 divisors (see below), whose sum is σ = 1935705408. Its totient is φ = 677635200.

The previous prime is 1218856349. The next prime is 1218856381. The reversal of 1218856353 is 3536588121.

It is not a de Polignac number, because 1218856353 - 2² = 1218856349 is a prime.

It is a super-2 number, since 2×1218856353² = 2971221618496921218, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1218856333) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 853426 + ... + 854852.

It is an arithmetic number, because the mean of its divisors is an integer number (40327196).

Almost surely, 2^1218856353 is an apocalyptic number.

1218856353 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1218856353 is a deficient number, since it is larger than the sum of its proper divisors (716849055).

1218856353 is a wasteful number, since it uses less digits than its factorization.

1218856353 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1646 (or 1635 counting only the distinct ones).

The product of its digits is 172800, while the sum is 42.

The square root of 1218856353 is about 34912.1232954972. The cubic root of 1218856353 is about 1068.1957402947.

The spelling of 1218856353 in words is "one billion, two hundred eighteen million, eight hundred fifty-six thousand, three hundred fifty-three".