771721064 has 16 divisors (see below), whose sum is σ = 1456690500. Its totient is φ = 383270272.

The previous prime is 771721063. The next prime is 771721073. The reversal of 771721064 is 460127177.

It can be written as a sum of positive squares in 2 ways, for example, as 769618564 + 2102500 = 27742^2 + 1450^2 .

It is not an unprimeable number, because it can be changed into a prime (771721061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 322517 + ... + 324900.

Almost surely, 2^771721064 is an apocalyptic number.

It is an amenable number.

771721064 is a deficient number, since it is larger than the sum of its proper divisors (684969436).

771721064 is a wasteful number, since it uses less digits than its factorization.

771721064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 647572 (or 647568 counting only the distinct ones).

The product of its (nonzero) digits is 16464, while the sum is 35.

The square root of 771721064 is about 27779.8679622492. The cubic root of 771721064 is about 917.2480239186.

The spelling of 771721064 in words is "seven hundred seventy-one million, seven hundred twenty-one thousand, sixty-four".