78309000 has 384 divisors, whose sum is σ = 332916480. Its totient is φ = 16128000.

The previous prime is 78308999. The next prime is 78309059. The reversal of 78309000 is 90387.

It is a happy number.

It is a super-2 number, since 2×78309000² = 12264598962000000, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 692944 + ... + 693056.

It is an arithmetic number, because the mean of its divisors is an integer number (866970).

Almost surely, 2^78309000 is an apocalyptic number.

78309000 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78309000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (166458240).

78309000 is an abundant number, since it is smaller than the sum of its proper divisors (254607480).

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

78309000 is a wasteful number, since it uses less digits than its factorization.

78309000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158 (or 141 counting only the distinct ones).

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

The square root of 78309000 is about 8849.2372552667. The cubic root of 78309000 is about 427.8293348153.

Adding to 78309000 its reverse (90387), we get a palindrome (78399387).

The spelling of 78309000 in words is "seventy-eight million, three hundred nine thousand".