77313121 has 2 divisors, whose sum is σ = 77313122. Its totient is φ = 77313120.

The previous prime is 77313079. The next prime is 77313133. The reversal of 77313121 is 12131377.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65028096 + 12285025 = 8064^2 + 3505^2 .

It is an emirp because it is prime and its reverse (12131377) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77313121 - 2⁷ = 77312993 is a prime.

It is not a weakly prime, because it can be changed into another prime (77316121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38656560 + 38656561.

It is an arithmetic number, because the mean of its divisors is an integer number (38656561).

Almost surely, 2^77313121 is an apocalyptic number.

It is an amenable number.

77313121 is a deficient number, since it is larger than the sum of its proper divisors (1).

77313121 is an equidigital number, since it uses as much as digits as its factorization.

77313121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 882, while the sum is 25.

The square root of 77313121 is about 8792.7880106369. The cubic root of 77313121 is about 426.0079807038.

Adding to 77313121 its reverse (12131377), we get a palindrome (89444498).

The spelling of 77313121 in words is "seventy-seven million, three hundred thirteen thousand, one hundred twenty-one".