1630720761 has 4 divisors (see below), whose sum is σ = 2174294352. Its totient is φ = 1087147172.

The previous prime is 1630720759. The next prime is 1630720783. The reversal of 1630720761 is 1670270361.

1630720761 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

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 a cyclic number.

It is not a de Polignac number, because 1630720761 - 2¹ = 1630720759 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1630720361) 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, 271786791 + ... + 271786796.

It is an arithmetic number, because the mean of its divisors is an integer number (543573588).

Almost surely, 2^1630720761 is an apocalyptic number.

It is an amenable number.

1630720761 is a deficient number, since it is larger than the sum of its proper divisors (543573591).

1630720761 is an equidigital number, since it uses as much as digits as its factorization.

1630720761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 543573590.

The product of its (nonzero) digits is 10584, while the sum is 33.

The square root of 1630720761 is about 40382.1837076699. The cubic root of 1630720761 is about 1177.0453612426.

The spelling of 1630720761 in words is "one billion, six hundred thirty million, seven hundred twenty thousand, seven hundred sixty-one".