78628999 has 2 divisors, whose sum is σ = 78629000. Its totient is φ = 78628998.

The previous prime is 78628967. The next prime is 78629027. The reversal of 78628999 is 99982687.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78628999 - 2⁵ = 78628967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78628909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39314499 + 39314500.

It is an arithmetic number, because the mean of its divisors is an integer number (39314500).

Almost surely, 2^78628999 is an apocalyptic number.

78628999 is a deficient number, since it is larger than the sum of its proper divisors (1).

78628999 is an equidigital number, since it uses as much as digits as its factorization.

78628999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3919104, while the sum is 58.

The square root of 78628999 is about 8867.2994197783. The cubic root of 78628999 is about 428.4112981502.

It can be divided in two parts, 7862 and 8999, that added together give a palindrome (16861).

The spelling of 78628999 in words is "seventy-eight million, six hundred twenty-eight thousand, nine hundred ninety-nine".