1821988450 has 24 divisors (see below), whose sum is σ = 3397782528. Its totient is φ = 726884880.

The previous prime is 1821988391. The next prime is 1821988459. The reversal of 1821988450 is 548891281.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 1821988450.

It is not an unprimeable number, because it can be changed into a prime (1821988459) 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, 28422 + ... + 66721.

It is an arithmetic number, because the mean of its divisors is an integer number (141574272).

Almost surely, 2^1821988450 is an apocalyptic number.

1821988450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1821988450 is a deficient number, since it is larger than the sum of its proper divisors (1575794078).

1821988450 is a wasteful number, since it uses less digits than its factorization.

1821988450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95538 (or 95533 counting only the distinct ones).

The product of its (nonzero) digits is 184320, while the sum is 46.

The square root of 1821988450 is about 42684.7566468406. The cubic root of 1821988450 is about 1221.3736319724.

The spelling of 1821988450 in words is "one billion, eight hundred twenty-one million, nine hundred eighty-eight thousand, four hundred fifty".