78629791 has 2 divisors, whose sum is σ = 78629792. Its totient is φ = 78629790.

The previous prime is 78629767. The next prime is 78629827. The reversal of 78629791 is 19792687.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78629791 - 2¹⁵ = 78597023 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78629191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39314895 + 39314896.

It is an arithmetic number, because the mean of its divisors is an integer number (39314896).

Almost surely, 2^78629791 is an apocalyptic number.

78629791 is a deficient number, since it is larger than the sum of its proper divisors (1).

78629791 is an equidigital number, since it uses as much as digits as its factorization.

78629791 is an evil number, because the sum of its binary digits is even.

The product of its digits is 381024, while the sum is 49.

The square root of 78629791 is about 8867.3440781330. The cubic root of 78629791 is about 428.4127365534.

The spelling of 78629791 in words is "seventy-eight million, six hundred twenty-nine thousand, seven hundred ninety-one".