1671666731 has 4 divisors (see below), whose sum is σ = 1910476272. Its totient is φ = 1432857192.

The previous prime is 1671666727. The next prime is 1671666757. The reversal of 1671666731 is 1376661761.

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 1671666731 - 2² = 1671666727 is a prime.

It is a super-2 number, since 2×1671666731² = 5588939319064452722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1671666761) 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, 119404760 + ... + 119404773.

It is an arithmetic number, because the mean of its divisors is an integer number (477619068).

Almost surely, 2^1671666731 is an apocalyptic number.

1671666731 is a deficient number, since it is larger than the sum of its proper divisors (238809541).

1671666731 is an equidigital number, since it uses as much as digits as its factorization.

1671666731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238809540.

The product of its digits is 190512, while the sum is 44.

The square root of 1671666731 is about 40886.0212175262. The cubic root of 1671666731 is about 1186.8155641639.

The spelling of 1671666731 in words is "one billion, six hundred seventy-one million, six hundred sixty-six thousand, seven hundred thirty-one".