78663420900 has 81 divisors (see below), whose sum is σ = 246592498971. Its totient is φ = 20974668480.

The previous prime is 78663420881. The next prime is 78663420919. The reversal of 78663420900 is 902436687.

The square root of 78663420900 is 280470.

It is a perfect power (a square), and thus also a powerful number.

78663420900 is a `hidden beast` number, since 7 + 8 + 6 + 634 + 2 + 0 + 9 + 0 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (78663420881) and next prime (78663420919).

It can be written as a sum of positive squares in 4 ways, for example, as 5555913444 + 73107507456 = 74538^2 + 270384^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 8409426 + ... + 8418774.

Almost surely, 2^78663420900 is an apocalyptic number.

78663420900 is the 280470-th square number.

It is an amenable number.

78663420900 is an abundant number, since it is smaller than the sum of its proper divisors (167929078071).

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

78663420900 is an equidigital number, since it uses as much as digits as its factorization.

78663420900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18718 (or 9359 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The spelling of 78663420900 in words is "seventy-eight billion, six hundred sixty-three million, four hundred twenty thousand, nine hundred".