766370721 has 4 divisors (see below), whose sum is σ = 1021827632. Its totient is φ = 510913812.

The previous prime is 766370707. The next prime is 766370771. The reversal of 766370721 is 127073667.

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 not a de Polignac number, because 766370721 - 2⁷ = 766370593 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 766370721.

It is not an unprimeable number, because it can be changed into a prime (766370771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 127728451 + ... + 127728456.

It is an arithmetic number, because the mean of its divisors is an integer number (255456908).

Almost surely, 2^766370721 is an apocalyptic number.

It is an amenable number.

766370721 is a deficient number, since it is larger than the sum of its proper divisors (255456911).

766370721 is a wasteful number, since it uses less digits than its factorization.

766370721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255456910.

The product of its (nonzero) digits is 74088, while the sum is 39.

The square root of 766370721 is about 27683.4015431630. The cubic root of 766370721 is about 915.1233456698.

The spelling of 766370721 in words is "seven hundred sixty-six million, three hundred seventy thousand, seven hundred twenty-one".