1668520371 has 16 divisors (see below), whose sum is σ = 2565010944. Its totient is φ = 945001344.

The previous prime is 1668520367. The next prime is 1668520391. The reversal of 1668520371 is 1730258661.

It is not a de Polignac number, because 1668520371 - 2² = 1668520367 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1668520391) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 349191 + ... + 353936.

It is an arithmetic number, because the mean of its divisors is an integer number (160313184).

Almost surely, 2^1668520371 is an apocalyptic number.

1668520371 is a deficient number, since it is larger than the sum of its proper divisors (896490573).

1668520371 is a wasteful number, since it uses less digits than its factorization.

1668520371 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 703250.

The product of its (nonzero) digits is 60480, while the sum is 39.

The square root of 1668520371 is about 40847.5258859089. The cubic root of 1668520371 is about 1186.0705005359.

The spelling of 1668520371 in words is "one billion, six hundred sixty-eight million, five hundred twenty thousand, three hundred seventy-one".