77020121 has 2 divisors, whose sum is σ = 77020122. Its totient is φ = 77020120.

The previous prime is 77020093. The next prime is 77020147. The reversal of 77020121 is 12102077.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60528400 + 16491721 = 7780^2 + 4061^2 .

It is a cyclic number.

It is not a de Polignac number, because 77020121 - 2⁶ = 77020057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 77020093 and 77020102.

It is not a weakly prime, because it can be changed into another prime (77020171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38510060 + 38510061.

It is an arithmetic number, because the mean of its divisors is an integer number (38510061).

Almost surely, 2^77020121 is an apocalyptic number.

It is an amenable number.

77020121 is a deficient number, since it is larger than the sum of its proper divisors (1).

77020121 is an equidigital number, since it uses as much as digits as its factorization.

77020121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 196, while the sum is 20.

The square root of 77020121 is about 8776.1108128829. The cubic root of 77020121 is about 425.4691400764.

Adding to 77020121 its reverse (12102077), we get a palindrome (89122198).

The spelling of 77020121 in words is "seventy-seven million, twenty thousand, one hundred twenty-one".