77890517 has 2 divisors, whose sum is σ = 77890518. Its totient is φ = 77890516.

The previous prime is 77890511. The next prime is 77890523. The reversal of 77890517 is 71509877.

It is a balanced prime because it is at equal distance from previous prime (77890511) and next prime (77890523).

It can be written as a sum of positive squares in only one way, i.e., 72063121 + 5827396 = 8489^2 + 2414^2 .

It is an emirp because it is prime and its reverse (71509877) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77890517 - 2²⁶ = 10781653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77890511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38945258 + 38945259.

It is an arithmetic number, because the mean of its divisors is an integer number (38945259).

Almost surely, 2^77890517 is an apocalyptic number.

It is an amenable number.

77890517 is a deficient number, since it is larger than the sum of its proper divisors (1).

77890517 is an equidigital number, since it uses as much as digits as its factorization.

77890517 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 123480, while the sum is 44.

The square root of 77890517 is about 8825.5604354624. The cubic root of 77890517 is about 427.0658670903.

The spelling of 77890517 in words is "seventy-seven million, eight hundred ninety thousand, five hundred seventeen".