3870921 has 8 divisors (see below), whose sum is σ = 5226880. Its totient is φ = 2547792.

The previous prime is 3870913. The next prime is 3870929. The reversal of 3870921 is 1290783.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (3870913) and next prime (3870929).

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

It is not a de Polignac number, because 3870921 - 2³ = 3870913 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3870929) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7930 + ... + 8403.

It is an arithmetic number, because the mean of its divisors is an integer number (653360).

Almost surely, 2^3870921 is an apocalyptic number.

It is an amenable number.

3870921 is a deficient number, since it is larger than the sum of its proper divisors (1355959).

3870921 is a wasteful number, since it uses less digits than its factorization.

3870921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16415.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 3870921 is about 1967.4656286705. The cubic root of 3870921 is about 157.0139006178.

The spelling of 3870921 in words is "three million, eight hundred seventy thousand, nine hundred twenty-one".