1821359898 has 32 divisors (see below), whose sum is σ = 4051300800. Its totient is φ = 606544848.

The previous prime is 1821359887. The next prime is 1821359909. The reversal of 1821359898 is 8989531281.

It is an interprime number because it is at equal distance from previous prime (1821359887) and next prime (1821359909).

It is a Harshad number since it is a multiple of its sum of digits (54).

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 15 ways as a sum of consecutive naturals, for example, 43593 + ... + 74451.

It is an arithmetic number, because the mean of its divisors is an integer number (126603150).

Almost surely, 2^1821359898 is an apocalyptic number.

1821359898 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1821359898 is an abundant number, since it is smaller than the sum of its proper divisors (2229940902).

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

1821359898 is a wasteful number, since it uses less digits than its factorization.

1821359898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31963 (or 31957 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 54.

The square root of 1821359898 is about 42677.3932896563. The cubic root of 1821359898 is about 1221.2331654514.

The spelling of 1821359898 in words is "one billion, eight hundred twenty-one million, three hundred fifty-nine thousand, eight hundred ninety-eight".