766547221 has 12 divisors (see below), whose sum is σ = 892133676. Its totient is φ = 655867520.

The previous prime is 766547219. The next prime is 766547233. The reversal of 766547221 is 122745667.

It can be written as a sum of positive squares in 2 ways, for example, as 370139121 + 396408100 = 19239^2 + 19910^2 .

It is not a de Polignac number, because 766547221 - 2¹ = 766547219 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 (766547021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 184270 + ... + 188383.

It is an arithmetic number, because the mean of its divisors is an integer number (74344473).

Almost surely, 2^766547221 is an apocalyptic number.

It is an amenable number.

766547221 is a deficient number, since it is larger than the sum of its proper divisors (125586455).

766547221 is a wasteful number, since it uses less digits than its factorization.

766547221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 372692 (or 372681 counting only the distinct ones).

The product of its digits is 141120, while the sum is 40.

The square root of 766547221 is about 27686.5891904366. The cubic root of 766547221 is about 915.1935931658.

The spelling of 766547221 in words is "seven hundred sixty-six million, five hundred forty-seven thousand, two hundred twenty-one".