3961651 has 2 divisors, whose sum is σ = 3961652. Its totient is φ = 3961650.

The previous prime is 3961649. The next prime is 3961669. The reversal of 3961651 is 1561693.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 3961651 - 2¹ = 3961649 is a prime.

Together with 3961649, it forms a pair of twin primes.

It is a zygodrome in base 2.

It is not a weakly prime, because it can be changed into another prime (3961631) 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, 1980825 + 1980826.

It is an arithmetic number, because the mean of its divisors is an integer number (1980826).

Almost surely, 2^3961651 is an apocalyptic number.

3961651 is a deficient number, since it is larger than the sum of its proper divisors (1).

3961651 is an equidigital number, since it uses as much as digits as its factorization.

3961651 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4860, while the sum is 31.

The square root of 3961651 is about 1990.3896603429. The cubic root of 3961651 is about 158.2311816314.

It can be divided in two parts, 396 and 1651, that multiplied together give a triangular number (653796 = T₁₁₄₃).

The spelling of 3961651 in words is "three million, nine hundred sixty-one thousand, six hundred fifty-one".