78355998 has 60 divisors (see below), whose sum is σ = 204261552. Its totient is φ = 22385160.

The previous prime is 78355967. The next prime is 78356011. The reversal of 78355998 is 89955387.

78355998 is a `hidden beast` number, since 7 + 83 + 559 + 9 + 8 = 666.

It is a super-2 number, since 2×78355998² = 12279324845152008, which contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 3003 + ... + 12873.

Almost surely, 2^78355998 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78355998, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102130776).

78355998 is an abundant number, since it is smaller than the sum of its proper divisors (125905554).

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

78355998 is a wasteful number, since it uses less digits than its factorization.

78355998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9899 (or 9883 counting only the distinct ones).

The product of its digits is 2721600, while the sum is 54.

The square root of 78355998 is about 8851.8923400593. The cubic root of 78355998 is about 427.9149065117.

The spelling of 78355998 in words is "seventy-eight million, three hundred fifty-five thousand, nine hundred ninety-eight".