78031493 has 2 divisors, whose sum is σ = 78031494. Its totient is φ = 78031492.

The previous prime is 78031451. The next prime is 78031507. The reversal of 78031493 is 39413087.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78021889 + 9604 = 8833^2 + 98^2 .

It is a cyclic number.

It is not a de Polignac number, because 78031493 - 2¹⁴ = 78015109 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78034493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39015746 + 39015747.

It is an arithmetic number, because the mean of its divisors is an integer number (39015747).

Almost surely, 2^78031493 is an apocalyptic number.

It is an amenable number.

78031493 is a deficient number, since it is larger than the sum of its proper divisors (1).

78031493 is an equidigital number, since it uses as much as digits as its factorization.

78031493 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 78031493 is about 8833.5436264276. The cubic root of 78031493 is about 427.3233642101.

The spelling of 78031493 in words is "seventy-eight million, thirty-one thousand, four hundred ninety-three".