625779448817 has 2 divisors, whose sum is σ = 625779448818. Its totient is φ = 625779448816.

The previous prime is 625779448793. The next prime is 625779448859. The reversal of 625779448817 is 718844977526.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 598791201856 + 26988246961 = 773816^2 + 164281^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-625779448817 is a prime.

It is a super-4 number, since 4×625779448817⁴ (a number of 48 digits) contains 4444 as substring.

It is not a weakly prime, because it can be changed into another prime (625779448897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 312889724408 + 312889724409.

It is an arithmetic number, because the mean of its divisors is an integer number (312889724409).

Almost surely, 2^625779448817 is an apocalyptic number.

It is an amenable number.

625779448817 is a deficient number, since it is larger than the sum of its proper divisors (1).

625779448817 is an equidigital number, since it uses as much as digits as its factorization.

625779448817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 189665280, while the sum is 68.

The spelling of 625779448817 in words is "six hundred twenty-five billion, seven hundred seventy-nine million, four hundred forty-eight thousand, eight hundred seventeen".