78180899 has 2 divisors, whose sum is σ = 78180900. Its totient is φ = 78180898.

The previous prime is 78180871. The next prime is 78180911. The reversal of 78180899 is 99808187.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78180899 - 2⁸ = 78180643 is a prime.

It is a super-2 number, since 2×78180899² = 12224505936896402, which contains 22 as substring.

It is a Chen prime.

It is a plaindrome in base 12.

It is not a weakly prime, because it can be changed into another prime (78180199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39090449 + 39090450.

It is an arithmetic number, because the mean of its divisors is an integer number (39090450).

Almost surely, 2^78180899 is an apocalyptic number.

78180899 is a deficient number, since it is larger than the sum of its proper divisors (1).

78180899 is an equidigital number, since it uses as much as digits as its factorization.

78180899 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 290304, while the sum is 50.

The square root of 78180899 is about 8841.9963243602. The cubic root of 78180899 is about 427.5959207033.

The spelling of 78180899 in words is "seventy-eight million, one hundred eighty thousand, eight hundred ninety-nine".