3731821 has 2 divisors, whose sum is σ = 3731822. Its totient is φ = 3731820.

The previous prime is 3731803. The next prime is 3731843. The reversal of 3731821 is 1281373.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3222025 + 509796 = 1795^2 + 714^2 .

It is a cyclic number.

It is not a de Polignac number, because 3731821 - 2¹⁷ = 3600749 is a prime.

It is equal to p₂₆₅₅₃₄ and since 3731821 and 265534 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3731801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1865910 + 1865911.

It is an arithmetic number, because the mean of its divisors is an integer number (1865911).

Almost surely, 2^3731821 is an apocalyptic number.

It is an amenable number.

3731821 is a deficient number, since it is larger than the sum of its proper divisors (1).

3731821 is an equidigital number, since it uses as much as digits as its factorization.

3731821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1008, while the sum is 25.

The square root of 3731821 is about 1931.7921730869. The cubic root of 3731821 is about 155.1101679496.

The spelling of 3731821 in words is "three million, seven hundred thirty-one thousand, eight hundred twenty-one".