78171400969 has 2 divisors, whose sum is σ = 78171400970. Its totient is φ = 78171400968.

The previous prime is 78171400939. The next prime is 78171400981. The reversal of 78171400969 is 96900417187.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75424383225 + 2747017744 = 274635^2 + 52412^2 .

It is a cyclic number.

It is not a de Polignac number, because 78171400969 - 2¹⁵ = 78171368201 is a prime.

It is a super-2 number, since 2×78171400969² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78171400939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39085700484 + 39085700485.

It is an arithmetic number, because the mean of its divisors is an integer number (39085700485).

Almost surely, 2^78171400969 is an apocalyptic number.

It is an amenable number.

78171400969 is a deficient number, since it is larger than the sum of its proper divisors (1).

78171400969 is an equidigital number, since it uses as much as digits as its factorization.

78171400969 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 762048, while the sum is 52.

The spelling of 78171400969 in words is "seventy-eight billion, one hundred seventy-one million, four hundred thousand, nine hundred sixty-nine".