78473749 has 2 divisors, whose sum is σ = 78473750. Its totient is φ = 78473748.

The previous prime is 78473699. The next prime is 78473767. The reversal of 78473749 is 94737487.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63123025 + 15350724 = 7945^2 + 3918^2 .

It is a cyclic number.

It is not a de Polignac number, because 78473749 - 2⁷ = 78473621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78473789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39236874 + 39236875.

It is an arithmetic number, because the mean of its divisors is an integer number (39236875).

Almost surely, 2^78473749 is an apocalyptic number.

It is an amenable number.

78473749 is a deficient number, since it is larger than the sum of its proper divisors (1).

78473749 is an equidigital number, since it uses as much as digits as its factorization.

78473749 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1185408, while the sum is 49.

The square root of 78473749 is about 8858.5410198294. The cubic root of 78473749 is about 428.1291517100.

The spelling of 78473749 in words is "seventy-eight million, four hundred seventy-three thousand, seven hundred forty-nine".