78643007253 has 12 divisors (see below), whose sum is σ = 113601386860. Its totient is φ = 52425933696.

The previous prime is 78643007249. The next prime is 78643007269. The reversal of 78643007253 is 35270034687.

It can be written as a sum of positive squares in 2 ways, for example, as 52053791409 + 26589215844 = 228153^2 + 163062^2 .

It is not a de Polignac number, because 78643007253 - 2² = 78643007249 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 78643007199 and 78643007208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78643007243) 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, 37876 + ... + 398397.

Almost surely, 2^78643007253 is an apocalyptic number.

It is an amenable number.

78643007253 is a deficient number, since it is larger than the sum of its proper divisors (34958379607).

78643007253 is a wasteful number, since it uses less digits than its factorization.

78643007253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456308 (or 456305 counting only the distinct ones).

The product of its (nonzero) digits is 846720, while the sum is 45.

The spelling of 78643007253 in words is "seventy-eight billion, six hundred forty-three million, seven thousand, two hundred fifty-three".