331081891 has 8 divisors (see below), whose sum is σ = 390585344. Its totient is φ = 274629960.

The previous prime is 331081889. The next prime is 331081901. The reversal of 331081891 is 198180133.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 331081891 - 2¹ = 331081889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (331081841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 762645 + ... + 763078.

It is an arithmetic number, because the mean of its divisors is an integer number (48823168).

Almost surely, 2^331081891 is an apocalyptic number.

331081891 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

331081891 is a deficient number, since it is larger than the sum of its proper divisors (59503453).

331081891 is a wasteful number, since it uses less digits than its factorization.

331081891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1525761.

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 331081891 is about 18195.6558276969. The cubic root of 331081891 is about 691.7966835341.

The spelling of 331081891 in words is "three hundred thirty-one million, eighty-one thousand, eight hundred ninety-one".