78729619 has 2 divisors, whose sum is σ = 78729620. Its totient is φ = 78729618.

The previous prime is 78729617. The next prime is 78729643. The reversal of 78729619 is 91692787.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78729619 - 2¹ = 78729617 is a prime.

It is a super-2 number, since 2×78729619² = 12396705815770322, which contains 22 as substring.

Together with 78729617, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (78729611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39364809 + 39364810.

It is an arithmetic number, because the mean of its divisors is an integer number (39364810).

Almost surely, 2^78729619 is an apocalyptic number.

78729619 is a deficient number, since it is larger than the sum of its proper divisors (1).

78729619 is an equidigital number, since it uses as much as digits as its factorization.

78729619 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 78729619 is about 8872.9712610827. The cubic root of 78729619 is about 428.5939634553.

The spelling of 78729619 in words is "seventy-eight million, seven hundred twenty-nine thousand, six hundred nineteen".