78625533257 has 2 divisors, whose sum is σ = 78625533258. Its totient is φ = 78625533256.

The previous prime is 78625533251. The next prime is 78625533293. The reversal of 78625533257 is 75233552687.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68750937616 + 9874595641 = 262204^2 + 99371^2 .

It is an emirp because it is prime and its reverse (75233552687) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78625533257 - 2⁴ = 78625533241 is a prime.

It is a super-2 number, since 2×78625533257² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78625533199 and 78625533208.

It is not a weakly prime, because it can be changed into another prime (78625533251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39312766628 + 39312766629.

It is an arithmetic number, because the mean of its divisors is an integer number (39312766629).

Almost surely, 2^78625533257 is an apocalyptic number.

It is an amenable number.

78625533257 is a deficient number, since it is larger than the sum of its proper divisors (1).

78625533257 is an equidigital number, since it uses as much as digits as its factorization.

78625533257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10584000, while the sum is 53.

The spelling of 78625533257 in words is "seventy-eight billion, six hundred twenty-five million, five hundred thirty-three thousand, two hundred fifty-seven".