78500491 has 2 divisors, whose sum is σ = 78500492. Its totient is φ = 78500490.

The previous prime is 78500489. The next prime is 78500507. The reversal of 78500491 is 19400587.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78500491 - 2¹ = 78500489 is a prime.

Together with 78500489, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (78501491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39250245 + 39250246.

It is an arithmetic number, because the mean of its divisors is an integer number (39250246).

Almost surely, 2^78500491 is an apocalyptic number.

78500491 is a deficient number, since it is larger than the sum of its proper divisors (1).

78500491 is an equidigital number, since it uses as much as digits as its factorization.

78500491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 78500491 is about 8860.0502820244. The cubic root of 78500491 is about 428.1777782874.

The spelling of 78500491 in words is "seventy-eight million, five hundred thousand, four hundred ninety-one".