3929981 has 4 divisors (see below), whose sum is σ = 4287264. Its totient is φ = 3572700.

The previous prime is 3929977. The next prime is 3930001. The reversal of 3929981 is 1899293.

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: 1899293 = 11 ⋅172663.

It is a cyclic number.

It is not a de Polignac number, because 3929981 - 2² = 3929977 is a prime.

It is a super-2 number, since 2×3929981² = 30889501320722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3929951) 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, 178625 + ... + 178646.

It is an arithmetic number, because the mean of its divisors is an integer number (1071816).

Almost surely, 2^3929981 is an apocalyptic number.

It is an amenable number.

3929981 is a deficient number, since it is larger than the sum of its proper divisors (357283).

3929981 is a wasteful number, since it uses less digits than its factorization.

3929981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 357282.

The product of its digits is 34992, while the sum is 41.

The square root of 3929981 is about 1982.4179680380. The cubic root of 3929981 is about 157.8084122262.

The spelling of 3929981 in words is "three million, nine hundred twenty-nine thousand, nine hundred eighty-one".