3991658 has 8 divisors (see below), whose sum is σ = 6531840. Its totient is φ = 1814380.

The previous prime is 3991649. The next prime is 3991667. The reversal of 3991658 is 8561993.

It is an interprime number because it is at equal distance from previous prime (3991649) and next prime (3991667).

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 90698 + ... + 90741.

It is an arithmetic number, because the mean of its divisors is an integer number (816480).

Almost surely, 2^3991658 is an apocalyptic number.

3991658 is a deficient number, since it is larger than the sum of its proper divisors (2540182).

3991658 is a wasteful number, since it uses less digits than its factorization.

3991658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181452.

The product of its digits is 58320, while the sum is 41.

The square root of 3991658 is about 1997.9134115371. The cubic root of 3991658 is about 158.6296775658.

The spelling of 3991658 in words is "three million, nine hundred ninety-one thousand, six hundred fifty-eight".