1660520971 has 8 divisors (see below), whose sum is σ = 1681832160. Its totient is φ = 1639268928.

The previous prime is 1660520929. The next prime is 1660520977. The reversal of 1660520971 is 1790250661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1660520971 - 2⁷ = 1660520843 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 1660520971.

It is not an unprimeable number, because it can be changed into a prime (1660520977) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43165 + ... + 72001.

It is an arithmetic number, because the mean of its divisors is an integer number (210229020).

Almost surely, 2^1660520971 is an apocalyptic number.

1660520971 is a deficient number, since it is larger than the sum of its proper divisors (21311189).

1660520971 is an equidigital number, since it uses as much as digits as its factorization.

1660520971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29573.

The product of its (nonzero) digits is 22680, while the sum is 37.

The square root of 1660520971 is about 40749.4904385319. The cubic root of 1660520971 is about 1184.1720010023.

The spelling of 1660520971 in words is "one billion, six hundred sixty million, five hundred twenty thousand, nine hundred seventy-one".