1851638268 has 12 divisors (see below), whose sum is σ = 4320489320. Its totient is φ = 617212752.

The previous prime is 1851638219. The next prime is 1851638279. The reversal of 1851638268 is 8628361581.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77151583 + ... + 77151606.

Almost surely, 2^1851638268 is an apocalyptic number.

It is an amenable number.

1851638268 is an abundant number, since it is smaller than the sum of its proper divisors (2468851052).

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

1851638268 is a wasteful number, since it uses less digits than its factorization.

1851638268 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154303196 (or 154303194 counting only the distinct ones).

The product of its digits is 552960, while the sum is 48.

The square root of 1851638268 is about 43030.6665995311. Note that the first 3 decimals coincide. The cubic root of 1851638268 is about 1227.9632867534.

The spelling of 1851638268 in words is "one billion, eight hundred fifty-one million, six hundred thirty-eight thousand, two hundred sixty-eight".