78390000 has 300 divisors, whose sum is σ = 299635336. Its totient is φ = 19008000.

The previous prime is 78389999. The next prime is 78390047. The reversal of 78390000 is 9387.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (300).

It is a super-2 number, since 2×78390000² = 12289984200000000, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

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 59 ways as a sum of consecutive naturals, for example, 1169967 + ... + 1170033.

Almost surely, 2^78390000 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78390000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (149817668).

78390000 is an abundant number, since it is smaller than the sum of its proper divisors (221245336).

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

78390000 is a wasteful number, since it uses less digits than its factorization.

78390000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114 (or 90 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 78390000 is about 8853.8127380242. The cubic root of 78390000 is about 427.9767943863.

Adding to 78390000 its reverse (9387), we get a palindrome (78399387).

The spelling of 78390000 in words is "seventy-eight million, three hundred ninety thousand".