3837721 has 2 divisors, whose sum is σ = 3837722. Its totient is φ = 3837720.

The previous prime is 3837703. The next prime is 3837727. The reversal of 3837721 is 1277383.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3686400 + 151321 = 1920^2 + 389^2 .

It is a cyclic number.

It is not a de Polignac number, because 3837721 - 2⁵ = 3837689 is a prime.

It is equal to p₂₇₂₄₉₇ and since 3837721 and 272497 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (3837727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1918860 + 1918861.

It is an arithmetic number, because the mean of its divisors is an integer number (1918861).

Almost surely, 2^3837721 is an apocalyptic number.

It is an amenable number.

3837721 is a deficient number, since it is larger than the sum of its proper divisors (1).

3837721 is an equidigital number, since it uses as much as digits as its factorization.

3837721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7056, while the sum is 31.

The square root of 3837721 is about 1959.0102092639. The cubic root of 3837721 is about 156.5637204073.

The spelling of 3837721 in words is "three million, eight hundred thirty-seven thousand, seven hundred twenty-one".