78621700 has 36 divisors (see below), whose sum is σ = 172198180. Its totient is φ = 31155840.

The previous prime is 78621691. The next prime is 78621703. The reversal of 78621700 is 712687.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 1498176 + 77123524 = 1224^2 + 8782^2 .

It is not an unprimeable number, because it can be changed into a prime (78621703) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7294 + ... + 14506.

Almost surely, 2^78621700 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 78621700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86099090).

78621700 is an abundant number, since it is smaller than the sum of its proper divisors (93576480).

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

78621700 is a wasteful number, since it uses less digits than its factorization.

78621700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7336 (or 7329 counting only the distinct ones).

The product of its (nonzero) digits is 4704, while the sum is 31.

The square root of 78621700 is about 8866.8878418530. The cubic root of 78621700 is about 428.3980415025.

The spelling of 78621700 in words is "seventy-eight million, six hundred twenty-one thousand, seven hundred".