3723921 has 16 divisors (see below), whose sum is σ = 5572800. Its totient is φ = 2457504.

The previous prime is 3723913. The next prime is 3723931. The reversal of 3723921 is 1293273.

It is not a de Polignac number, because 3723921 - 2³ = 3723913 is a prime.

It is a super-2 number, since 2×3723921² = 27735175228482, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

3723921 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3723931) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2245 + ... + 3533.

It is an arithmetic number, because the mean of its divisors is an integer number (348300).

Almost surely, 2^3723921 is an apocalyptic number.

It is an amenable number.

3723921 is a deficient number, since it is larger than the sum of its proper divisors (1848879).

3723921 is a wasteful number, since it uses less digits than its factorization.

3723921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1405 (or 1399 counting only the distinct ones).

The product of its digits is 2268, while the sum is 27.

The square root of 3723921 is about 1929.7463563899. The cubic root of 3723921 is about 155.0006382214. Note that the first 3 decimals are identical.

The spelling of 3723921 in words is "three million, seven hundred twenty-three thousand, nine hundred twenty-one".