78161647 has 2 divisors, whose sum is σ = 78161648. Its totient is φ = 78161646.

The previous prime is 78161609. The next prime is 78161683. The reversal of 78161647 is 74616187.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78161647 - 2⁷ = 78161519 is a prime.

It is a super-2 number, since 2×78161647² = 12218486123505218, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78161147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39080823 + 39080824.

It is an arithmetic number, because the mean of its divisors is an integer number (39080824).

Almost surely, 2^78161647 is an apocalyptic number.

78161647 is a deficient number, since it is larger than the sum of its proper divisors (1).

78161647 is an equidigital number, since it uses as much as digits as its factorization.

78161647 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 56448, while the sum is 40.

The square root of 78161647 is about 8840.9075891562. The cubic root of 78161647 is about 427.5608194080.

The spelling of 78161647 in words is "seventy-eight million, one hundred sixty-one thousand, six hundred forty-seven".