331101021 has 4 divisors (see below), whose sum is σ = 441468032. Its totient is φ = 220734012.

The previous prime is 331101013. The next prime is 331101037. The reversal of 331101021 is 120101133.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 331101021 - 2³ = 331101013 is a prime.

It is a super-2 number, since 2×331101021² = 219255772214484882, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 331100988 and 331101006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (331101521) 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 3 ways as a sum of consecutive naturals, for example, 55183501 + ... + 55183506.

It is an arithmetic number, because the mean of its divisors is an integer number (110367008).

Almost surely, 2^331101021 is an apocalyptic number.

It is an amenable number.

331101021 is a deficient number, since it is larger than the sum of its proper divisors (110367011).

331101021 is a wasteful number, since it uses less digits than its factorization.

331101021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110367010.

The product of its (nonzero) digits is 18, while the sum is 12.

The square root of 331101021 is about 18196.1814950280. The cubic root of 331101021 is about 691.8100073431.

Adding to 331101021 its reverse (120101133), we get a palindrome (451202154).

The spelling of 331101021 in words is "three hundred thirty-one million, one hundred one thousand, twenty-one".