772561 has 4 divisors (see below), whose sum is σ = 774324. Its totient is φ = 770800.

The previous prime is 772537. The next prime is 772567. The reversal of 772561 is 165277.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 342225 + 430336 = 585^2 + 656^2 .

It is a cyclic number.

It is not a de Polignac number, because 772561 - 2¹³ = 764369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (772567) 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, 351 + ... + 1291.

It is an arithmetic number, because the mean of its divisors is an integer number (193581).

2⁷⁷²⁵⁶¹ is an apocalyptic number.

It is an amenable number.

772561 is a deficient number, since it is larger than the sum of its proper divisors (1763).

772561 is an equidigital number, since it uses as much as digits as its factorization.

772561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1762.

The product of its digits is 2940, while the sum is 28.

The square root of 772561 is about 878.9544925649. The cubic root of 772561 is about 91.7580678782.

The spelling of 772561 in words is "seven hundred seventy-two thousand, five hundred sixty-one".