77204121 has 4 divisors (see below), whose sum is σ = 102938832. Its totient is φ = 51469412.

The previous prime is 77204081. The next prime is 77204137. The reversal of 77204121 is 12140277.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12140277 = 3 ⋅4046759.

It is a cyclic number.

It is not a de Polignac number, because 77204121 - 2⁷ = 77203993 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 77204091 and 77204100.

It is not an unprimeable number, because it can be changed into a prime (77204821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12867351 + ... + 12867356.

It is an arithmetic number, because the mean of its divisors is an integer number (25734708).

Almost surely, 2^77204121 is an apocalyptic number.

It is an amenable number.

77204121 is a deficient number, since it is larger than the sum of its proper divisors (25734711).

77204121 is a wasteful number, since it uses less digits than its factorization.

77204121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25734710.

The product of its (nonzero) digits is 784, while the sum is 24.

The square root of 77204121 is about 8786.5875628710. The cubic root of 77204121 is about 425.8076839172.

Adding to 77204121 its reverse (12140277), we get a palindrome (89344398).

The spelling of 77204121 in words is "seventy-seven million, two hundred four thousand, one hundred twenty-one".