78685450 has 12 divisors (see below), whose sum is σ = 146355030. Its totient is φ = 31474160.

The previous prime is 78685429. The next prime is 78685457. The reversal of 78685450 is 5458687.

It can be written as a sum of positive squares in 3 ways, for example, as 62932489 + 15752961 = 7933^2 + 3969^2 .

It is a junction number, because it is equal to n+sod(n) for n = 78685397 and 78685406.

It is not an unprimeable number, because it can be changed into a prime (78685457) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 786805 + ... + 786904.

Almost surely, 2^78685450 is an apocalyptic number.

78685450 is a deficient number, since it is larger than the sum of its proper divisors (67669580).

78685450 is a wasteful number, since it uses less digits than its factorization.

78685450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1573721 (or 1573716 counting only the distinct ones).

The product of its (nonzero) digits is 268800, while the sum is 43.

The square root of 78685450 is about 8870.4819485753. The cubic root of 78685450 is about 428.5137983354.

The spelling of 78685450 in words is "seventy-eight million, six hundred eighty-five thousand, four hundred fifty".