1921017898 has 8 divisors (see below), whose sum is σ = 2882623392. Its totient is φ = 960143436.

The previous prime is 1921017871. The next prime is 1921017907. The reversal of 1921017898 is 8987101291.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 176140 + ... + 186727.

It is an arithmetic number, because the mean of its divisors is an integer number (360327924).

Almost surely, 2^1921017898 is an apocalyptic number.

1921017898 is a deficient number, since it is larger than the sum of its proper divisors (961605494).

1921017898 is a wasteful number, since it uses less digits than its factorization.

1921017898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365516.

The product of its (nonzero) digits is 72576, while the sum is 46.

The square root of 1921017898 is about 43829.4181800306. The cubic root of 1921017898 is about 1243.1126056444.

The spelling of 1921017898 in words is "one billion, nine hundred twenty-one million, seventeen thousand, eight hundred ninety-eight".