1018194381 has 20 divisors (see below), whose sum is σ = 1521877984. Its totient is φ = 678407400.

The previous prime is 1018194343. The next prime is 1018194403. The reversal of 1018194381 is 1834918101.

1018194381 is a `hidden beast` number, since 10 + 181 + 94 + 381 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-1018194381 is a prime.

It is a super-2 number, since 2×1018194381² = 2073439594999946322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1018194341) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 238536 + ... + 242766.

Almost surely, 2^1018194381 is an apocalyptic number.

It is an amenable number.

1018194381 is a deficient number, since it is larger than the sum of its proper divisors (503683603).

1018194381 is an equidigital number, since it uses as much as digits as its factorization.

1018194381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7214 (or 7205 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 36.

The square root of 1018194381 is about 31909.1582621667. The cubic root of 1018194381 is about 1006.0283792834.

The spelling of 1018194381 in words is "one billion, eighteen million, one hundred ninety-four thousand, three hundred eighty-one".