78811619 has 2 divisors, whose sum is σ = 78811620. Its totient is φ = 78811618.

The previous prime is 78811597. The next prime is 78811657. The reversal of 78811619 is 91611887.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78811619 - 2¹² = 78807523 is a prime.

It is a super-2 number, since 2×78811619² = 12422542578802322, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (78811679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39405809 + 39405810.

It is an arithmetic number, because the mean of its divisors is an integer number (39405810).

Almost surely, 2^78811619 is an apocalyptic number.

78811619 is a deficient number, since it is larger than the sum of its proper divisors (1).

78811619 is an equidigital number, since it uses as much as digits as its factorization.

78811619 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24192, while the sum is 41.

The square root of 78811619 is about 8877.5908331033. The cubic root of 78811619 is about 428.7427109913.

The spelling of 78811619 in words is "seventy-eight million, eight hundred eleven thousand, six hundred nineteen".