775670221 has 4 divisors (see below), whose sum is σ = 802417500. Its totient is φ = 748922944.

The previous prime is 775670201. The next prime is 775670321. The reversal of 775670221 is 122076577.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 323640100 + 452030121 = 17990^2 + 21261^2 .

It is a cyclic number.

It is not a de Polignac number, because 775670221 - 2⁹ = 775669709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (775670201) 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, 13373596 + ... + 13373653.

It is an arithmetic number, because the mean of its divisors is an integer number (200604375).

Almost surely, 2^775670221 is an apocalyptic number.

It is an amenable number.

775670221 is a deficient number, since it is larger than the sum of its proper divisors (26747279).

775670221 is a wasteful number, since it uses less digits than its factorization.

775670221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26747278.

The product of its (nonzero) digits is 41160, while the sum is 37.

The square root of 775670221 is about 27850.8567372711. The cubic root of 775670221 is about 918.8099850942.

It can be divided in two parts, 7756 and 70221, that added together give a palindrome (77977).

The spelling of 775670221 in words is "seven hundred seventy-five million, six hundred seventy thousand, two hundred twenty-one".