78209000 has 64 divisors (see below), whose sum is σ = 184401360. Its totient is φ = 31046400.

The previous prime is 78208981. The next prime is 78209023. The reversal of 78209000 is 90287.

It can be written as a sum of positive squares in 8 ways, for example, as 24068836 + 54140164 = 4906^2 + 7358^2 .

It is a super-2 number, since 2×78209000² = 12233295362000000, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 196802 + ... + 197198.

Almost surely, 2^78209000 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 78209000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92200680).

78209000 is an abundant number, since it is smaller than the sum of its proper divisors (106192360).

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

78209000 is a wasteful number, since it uses less digits than its factorization.

78209000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 615 (or 601 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 26.

The square root of 78209000 is about 8843.5852458152. The cubic root of 78209000 is about 427.6471456349.

Adding to 78209000 its reverse (90287), we get a palindrome (78299287).

The spelling of 78209000 in words is "seventy-eight million, two hundred nine thousand".