1821127994 has 24 divisors (see below), whose sum is σ = 3263584800. Its totient is φ = 746546328.

The previous prime is 1821127981. The next prime is 1821127999. The reversal of 1821127994 is 4997211281.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (1821127999) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 115544 + ... + 130355.

It is an arithmetic number, because the mean of its divisors is an integer number (135982700).

Almost surely, 2^1821127994 is an apocalyptic number.

1821127994 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

1821127994 is a deficient number, since it is larger than the sum of its proper divisors (1442456806).

1821127994 is a wasteful number, since it uses less digits than its factorization.

1821127994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245954 (or 245931 counting only the distinct ones).

The product of its digits is 72576, while the sum is 44.

The square root of 1821127994 is about 42674.6762612208. The cubic root of 1821127994 is about 1221.1813322256.

The spelling of 1821127994 in words is "one billion, eight hundred twenty-one million, one hundred twenty-seven thousand, nine hundred ninety-four".