78291071 has 2 divisors, whose sum is σ = 78291072. Its totient is φ = 78291070.

The previous prime is 78291023. The next prime is 78291127. The reversal of 78291071 is 17019287.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78291071 - 2²² = 74096767 is a prime.

It is a super-2 number, since 2×78291071² = 12258983596654082, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78290071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39145535 + 39145536.

It is an arithmetic number, because the mean of its divisors is an integer number (39145536).

Almost surely, 2^78291071 is an apocalyptic number.

78291071 is a deficient number, since it is larger than the sum of its proper divisors (1).

78291071 is an equidigital number, since it uses as much as digits as its factorization.

78291071 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7056, while the sum is 35.

The square root of 78291071 is about 8848.2241721150. The cubic root of 78291071 is about 427.7966815331.

The spelling of 78291071 in words is "seventy-eight million, two hundred ninety-one thousand, seventy-one".