77956121 has 2 divisors, whose sum is σ = 77956122. Its totient is φ = 77956120.

The previous prime is 77956097. The next prime is 77956139. The reversal of 77956121 is 12165977.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68890000 + 9066121 = 8300^2 + 3011^2 .

It is a cyclic number.

It is not a de Polignac number, because 77956121 - 2¹⁴ = 77939737 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (77956141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38978060 + 38978061.

It is an arithmetic number, because the mean of its divisors is an integer number (38978061).

Almost surely, 2^77956121 is an apocalyptic number.

It is an amenable number.

77956121 is a deficient number, since it is larger than the sum of its proper divisors (1).

77956121 is an equidigital number, since it uses as much as digits as its factorization.

77956121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 26460, while the sum is 38.

The square root of 77956121 is about 8829.2763576637. The cubic root of 77956121 is about 427.1857334873.

The spelling of 77956121 in words is "seventy-seven million, nine hundred fifty-six thousand, one hundred twenty-one".