78305971 has 4 divisors (see below), whose sum is σ = 79408944. Its totient is φ = 77203000.

The previous prime is 78305959. The next prime is 78305987. The reversal of 78305971 is 17950387.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 78305971 - 2⁵ = 78305939 is a prime.

It is a super-2 number, since 2×78305971² = 12263650188505682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78305911) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 551380 + ... + 551521.

It is an arithmetic number, because the mean of its divisors is an integer number (19852236).

Almost surely, 2^78305971 is an apocalyptic number.

78305971 is a gapful number since it is divisible by the number (71) formed by its first and last digit.

78305971 is a deficient number, since it is larger than the sum of its proper divisors (1102973).

78305971 is a wasteful number, since it uses less digits than its factorization.

78305971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1102972.

The product of its (nonzero) digits is 52920, while the sum is 40.

The square root of 78305971 is about 8849.0661089179. The cubic root of 78305971 is about 427.8238185836.

The spelling of 78305971 in words is "seventy-eight million, three hundred five thousand, nine hundred seventy-one".