1213864128 has 42 divisors (see below), whose sum is σ = 3479324004. Its totient is φ = 404621184.

The previous prime is 1213864109. The next prime is 1213864181. The reversal of 1213864128 is 8214683121.

1213864128 is a `hidden beast` number, since 1 + 2 + 1 + 3 + 8 + 641 + 2 + 8 = 666.

It is a super-2 number, since 2×1213864128² = 2946932242490400768, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 1213864092 and 1213864101.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1053126 + ... + 1054277.

Almost surely, 2^1213864128 is an apocalyptic number.

1213864128 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1213864128 is an abundant number, since it is smaller than the sum of its proper divisors (2265459876).

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

1213864128 is a wasteful number, since it uses less digits than its factorization.

1213864128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2107421 (or 2107408 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 1213864128 is about 34840.5529232818. The cubic root of 1213864128 is about 1066.7353629368.

The spelling of 1213864128 in words is "one billion, two hundred thirteen million, eight hundred sixty-four thousand, one hundred twenty-eight".