78381241 has 2 divisors, whose sum is σ = 78381242. Its totient is φ = 78381240.

The previous prime is 78381239. The next prime is 78381253. The reversal of 78381241 is 14218387.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46785600 + 31595641 = 6840^2 + 5621^2 .

It is a cyclic number.

It is not a de Polignac number, because 78381241 - 2¹ = 78381239 is a prime.

It is a super-2 number, since 2×78381241² = 12287237881400162, which contains 22 as substring.

Together with 78381239, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 78381197 and 78381206.

It is not a weakly prime, because it can be changed into another prime (78381841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39190620 + 39190621.

It is an arithmetic number, because the mean of its divisors is an integer number (39190621).

Almost surely, 2^78381241 is an apocalyptic number.

It is an amenable number.

78381241 is a deficient number, since it is larger than the sum of its proper divisors (1).

78381241 is an equidigital number, since it uses as much as digits as its factorization.

78381241 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10752, while the sum is 34.

The square root of 78381241 is about 8853.3180785511. The cubic root of 78381241 is about 427.9608536270.

The spelling of 78381241 in words is "seventy-eight million, three hundred eighty-one thousand, two hundred forty-one".