771221 has 4 divisors (see below), whose sum is σ = 841344. Its totient is φ = 701100.

The previous prime is 771217. The next prime is 771227. The reversal of 771221 is 122177.

771221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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.

It is a cyclic number.

It is not a de Polignac number, because 771221 - 2² = 771217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 771193 and 771202.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 771221.

It is not an unprimeable number, because it can be changed into a prime (771227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35045 + ... + 35066.

It is an arithmetic number, because the mean of its divisors is an integer number (210336).

2⁷⁷¹²²¹ is an apocalyptic number.

It is an amenable number.

771221 is a deficient number, since it is larger than the sum of its proper divisors (70123).

771221 is a wasteful number, since it uses less digits than its factorization.

771221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70122.

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

The square root of 771221 is about 878.1918924700. The cubic root of 771221 is about 91.7049859994.

Adding to 771221 its reverse (122177), we get a palindrome (893398).

The spelling of 771221 in words is "seven hundred seventy-one thousand, two hundred twenty-one", and thus it is an iban number.