77122221 has 16 divisors (see below), whose sum is σ = 112768320. Its totient is φ = 46494720.

The previous prime is 77122219. The next prime is 77122229. The reversal of 77122221 is 12222177.

It is not a de Polignac number, because 77122221 - 2¹ = 77122219 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 77122191 and 77122200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77122229) 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 in 15 ways as a sum of consecutive naturals, for example, 315 + ... + 12423.

It is an arithmetic number, because the mean of its divisors is an integer number (7048020).

Almost surely, 2^77122221 is an apocalyptic number.

It is an amenable number.

77122221 is a deficient number, since it is larger than the sum of its proper divisors (35646099).

77122221 is a wasteful number, since it uses less digits than its factorization.

77122221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12316.

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

The square root of 77122221 is about 8781.9258138520. The cubic root of 77122221 is about 425.6570616113.

Adding to 77122221 its reverse (12222177), we get a palindrome (89344398).

The spelling of 77122221 in words is "seventy-seven million, one hundred twenty-two thousand, two hundred twenty-one".