1660643071 has 4 divisors (see below), whose sum is σ = 1665168352. Its totient is φ = 1656117792.

The previous prime is 1660643059. The next prime is 1660643081. The reversal of 1660643071 is 1703460661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1660643071 - 2¹⁷ = 1660511999 is a prime.

It is a super-2 number, since 2×1660643071² = 5515470818520622082, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1660643021) 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, 2262090 + ... + 2262823.

It is an arithmetic number, because the mean of its divisors is an integer number (416292088).

Almost surely, 2^1660643071 is an apocalyptic number.

1660643071 is a deficient number, since it is larger than the sum of its proper divisors (4525281).

1660643071 is an equidigital number, since it uses as much as digits as its factorization.

1660643071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4525280.

The product of its (nonzero) digits is 18144, while the sum is 34.

The square root of 1660643071 is about 40750.9885892355. The cubic root of 1660643071 is about 1184.2010247967.

The spelling of 1660643071 in words is "one billion, six hundred sixty million, six hundred forty-three thousand, seventy-one".