78781250 has 28 divisors (see below), whose sum is σ = 147771546. Its totient is φ = 31500000.

The previous prime is 78781243. The next prime is 78781253. The reversal of 78781250 is 5218787.

It can be written as a sum of positive squares in 7 ways, for example, as 68277169 + 10504081 = 8263^2 + 3241^2 .

It is an alternating number because its digits alternate between odd and even.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78781253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 29990 + ... + 32510.

Almost surely, 2^78781250 is an apocalyptic number.

78781250 is a deficient number, since it is larger than the sum of its proper divisors (68990296).

78781250 is an frugal number, since it uses more digits than its factorization.

78781250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2553 (or 2528 counting only the distinct ones).

The product of its (nonzero) digits is 31360, while the sum is 38.

The square root of 78781250 is about 8875.8802380384. The cubic root of 78781250 is about 428.6876338325.

The spelling of 78781250 in words is "seventy-eight million, seven hundred eighty-one thousand, two hundred fifty".