78490057 has 2 divisors, whose sum is σ = 78490058. Its totient is φ = 78490056.

The previous prime is 78490051. The next prime is 78490067. The reversal of 78490057 is 75009487.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 76370121 + 2119936 = 8739^2 + 1456^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78490057 is a prime.

It is not a weakly prime, because it can be changed into another prime (78490051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39245028 + 39245029.

It is an arithmetic number, because the mean of its divisors is an integer number (39245029).

Almost surely, 2^78490057 is an apocalyptic number.

It is an amenable number.

78490057 is a deficient number, since it is larger than the sum of its proper divisors (1).

78490057 is an equidigital number, since it uses as much as digits as its factorization.

78490057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 70560, while the sum is 40.

The square root of 78490057 is about 8859.4614396136. The cubic root of 78490057 is about 428.1588068354.

The spelling of 78490057 in words is "seventy-eight million, four hundred ninety thousand, fifty-seven".