78171943 has 2 divisors, whose sum is σ = 78171944. Its totient is φ = 78171942.

The previous prime is 78171937. The next prime is 78171959. The reversal of 78171943 is 34917187.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78171943 - 2⁵ = 78171911 is a prime.

It is a super-2 number, since 2×78171943² = 12221705344790498, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78171896 and 78171905.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78171983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39085971 + 39085972.

It is an arithmetic number, because the mean of its divisors is an integer number (39085972).

Almost surely, 2^78171943 is an apocalyptic number.

78171943 is a deficient number, since it is larger than the sum of its proper divisors (1).

78171943 is an equidigital number, since it uses as much as digits as its factorization.

78171943 is an evil number, because the sum of its binary digits is even.

The product of its digits is 42336, while the sum is 40.

The square root of 78171943 is about 8841.4898631396. The cubic root of 78171943 is about 427.5795923531.

The spelling of 78171943 in words is "seventy-eight million, one hundred seventy-one thousand, nine hundred forty-three".