1321099998 has 16 divisors (see below), whose sum is σ = 2668361616. Its totient is φ = 436006400.

The previous prime is 1321099993. The next prime is 1321100009. The reversal of 1321099998 is 8999901231.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1321099998.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321099993) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 1089411 + ... + 1090622.

It is an arithmetic number, because the mean of its divisors is an integer number (166772601).

Almost surely, 2^1321099998 is an apocalyptic number.

1321099998 is an abundant number, since it is smaller than the sum of its proper divisors (1347261618).

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

1321099998 is a wasteful number, since it uses less digits than its factorization.

1321099998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2180139.

The product of its (nonzero) digits is 314928, while the sum is 51.

The square root of 1321099998 is about 36346.9393209387. The cubic root of 1321099998 is about 1097.2659368050.

The spelling of 1321099998 in words is "one billion, three hundred twenty-one million, ninety-nine thousand, nine hundred ninety-eight".