7801998 has 8 divisors (see below), whose sum is σ = 15604008. Its totient is φ = 2600664.

The previous prime is 7801993. The next prime is 7801999. The reversal of 7801998 is 8991087.

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

7801998 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7801993) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 650161 + ... + 650172.

It is an arithmetic number, because the mean of its divisors is an integer number (1950501).

Almost surely, 2^7801998 is an apocalyptic number.

7801998 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

7801998 is a wasteful number, since it uses less digits than its factorization.

7801998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1300338.

The product of its (nonzero) digits is 36288, while the sum is 42.

The square root of 7801998 is about 2793.2056852298. The cubic root of 7801998 is about 198.3361802352.

The spelling of 7801998 in words is "seven million, eight hundred one thousand, nine hundred ninety-eight".