77385421 has 2 divisors, whose sum is σ = 77385422. Its totient is φ = 77385420.

The previous prime is 77385401. The next prime is 77385431. The reversal of 77385421 is 12458377.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41744521 + 35640900 = 6461^2 + 5970^2 .

It is a cyclic number.

It is not a de Polignac number, because 77385421 - 2¹³ = 77377229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77385401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38692710 + 38692711.

It is an arithmetic number, because the mean of its divisors is an integer number (38692711).

Almost surely, 2^77385421 is an apocalyptic number.

It is an amenable number.

77385421 is a deficient number, since it is larger than the sum of its proper divisors (1).

77385421 is an equidigital number, since it uses as much as digits as its factorization.

77385421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47040, while the sum is 37.

The square root of 77385421 is about 8796.8983738588. The cubic root of 77385421 is about 426.1407342844.

The spelling of 77385421 in words is "seventy-seven million, three hundred eighty-five thousand, four hundred twenty-one".