78441551 has 2 divisors, whose sum is σ = 78441552. Its totient is φ = 78441550.

The previous prime is 78441541. The next prime is 78441611. The reversal of 78441551 is 15514487.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78441551 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78441541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39220775 + 39220776.

It is an arithmetic number, because the mean of its divisors is an integer number (39220776).

Almost surely, 2^78441551 is an apocalyptic number.

78441551 is a deficient number, since it is larger than the sum of its proper divisors (1).

78441551 is an equidigital number, since it uses as much as digits as its factorization.

78441551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22400, while the sum is 35.

The square root of 78441551 is about 8856.7234912241. The cubic root of 78441551 is about 428.0705895013.

The spelling of 78441551 in words is "seventy-eight million, four hundred forty-one thousand, five hundred fifty-one".