77855243 has 2 divisors, whose sum is σ = 77855244. Its totient is φ = 77855242.

The previous prime is 77855237. The next prime is 77855249. The reversal of 77855243 is 34255877.

It is a balanced prime because it is at equal distance from previous prime (77855237) and next prime (77855249).

It is an emirp because it is prime and its reverse (34255877) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77855243 is a prime.

It is a super-2 number, since 2×77855243² = 12122877725178098, which contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 77855243.

It is not a weakly prime, because it can be changed into another prime (77855249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38927621 + 38927622.

It is an arithmetic number, because the mean of its divisors is an integer number (38927622).

Almost surely, 2^77855243 is an apocalyptic number.

77855243 is a deficient number, since it is larger than the sum of its proper divisors (1).

77855243 is an equidigital number, since it uses as much as digits as its factorization.

77855243 is an evil number, because the sum of its binary digits is even.

The product of its digits is 235200, while the sum is 41.

The square root of 77855243 is about 8823.5618091562. The cubic root of 77855243 is about 427.0013894252.

The spelling of 77855243 in words is "seventy-seven million, eight hundred fifty-five thousand, two hundred forty-three".