3961581 has 16 divisors (see below), whose sum is σ = 5733504. Its totient is φ = 2418624.

The previous prime is 3961579. The next prime is 3961597. The reversal of 3961581 is 1851693.

It is not a de Polignac number, because 3961581 - 2¹ = 3961579 is a prime.

It is a super-2 number, since 2×3961581² = 31388248039122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3961501) 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, 5800 + ... + 6446.

It is an arithmetic number, because the mean of its divisors is an integer number (358344).

Almost surely, 2^3961581 is an apocalyptic number.

It is an amenable number.

3961581 is a deficient number, since it is larger than the sum of its proper divisors (1771923).

3961581 is a wasteful number, since it uses less digits than its factorization.

3961581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 820.

The product of its digits is 6480, while the sum is 33.

The square root of 3961581 is about 1990.3720757687. The cubic root of 3961581 is about 158.2302496759.

The spelling of 3961581 in words is "three million, nine hundred sixty-one thousand, five hundred eighty-one".