78131047 has 2 divisors, whose sum is σ = 78131048. Its totient is φ = 78131046.

The previous prime is 78130973. The next prime is 78131071. The reversal of 78131047 is 74013187.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78131047 - 2¹⁹ = 77606759 is a prime.

It is a super-2 number, since 2×78131047² = 12208921010632418, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78131147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39065523 + 39065524.

It is an arithmetic number, because the mean of its divisors is an integer number (39065524).

Almost surely, 2^78131047 is an apocalyptic number.

78131047 is a deficient number, since it is larger than the sum of its proper divisors (1).

78131047 is an equidigital number, since it uses as much as digits as its factorization.

78131047 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4704, while the sum is 31.

The square root of 78131047 is about 8839.1768281894. The cubic root of 78131047 is about 427.5050159575.

The spelling of 78131047 in words is "seventy-eight million, one hundred thirty-one thousand, forty-seven".