78966900 has 90 divisors (see below), whose sum is σ = 256005750. Its totient is φ = 21055680.

The previous prime is 78966893. The next prime is 78966911. The reversal of 78966900 is 966987.

It can be written as a sum of positive squares in 3 ways, for example, as 219024 + 78747876 = 468^2 + 8874^2 .

It is a tau number, because it is divible by the number of its divisors (90).

It is a super-2 number, since 2×78966900² = 12471542591220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 3226 + ... + 12974.

Almost surely, 2^78966900 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 78966900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (128002875).

78966900 is an abundant number, since it is smaller than the sum of its proper divisors (177038850).

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

78966900 is a wasteful number, since it uses less digits than its factorization.

78966900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9775 (or 9759 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 45.

The square root of 78966900 is about 8886.3322017579. The cubic root of 78966900 is about 429.0241074036.

The spelling of 78966900 in words is "seventy-eight million, nine hundred sixty-six thousand, nine hundred".