331628681 has 4 divisors (see below), whose sum is σ = 331847952. Its totient is φ = 331409412.

The previous prime is 331628677. The next prime is 331628683. The reversal of 331628681 is 186826133.

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, and also an emirpimes, since its reverse is a distinct semiprime: 186826133 = 13 ⋅14371241.

It is a cyclic number.

It is not a de Polignac number, because 331628681 - 2² = 331628677 is a prime.

It is a super-2 number, since 2×331628681² = 219955164123599522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (331628683) 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, 107351 + ... + 110396.

It is an arithmetic number, because the mean of its divisors is an integer number (82961988).

Almost surely, 2^331628681 is an apocalyptic number.

It is an amenable number.

331628681 is a deficient number, since it is larger than the sum of its proper divisors (219271).

331628681 is a wasteful number, since it uses less digits than its factorization.

331628681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219270.

The product of its digits is 41472, while the sum is 38.

The square root of 331628681 is about 18210.6749188491. The cubic root of 331628681 is about 692.1773138960.

The spelling of 331628681 in words is "three hundred thirty-one million, six hundred twenty-eight thousand, six hundred eighty-one".